// SPDX-License-Identifier: GPL-2.0 /* * Copyright (C) 1991, 1992 Linus Torvalds */ /* * Hopefully this will be a rather complete VT102 implementation. * * Beeping thanks to John T Kohl. * * Virtual Consoles, Screen Blanking, Screen Dumping, Color, Graphics * Chars, and VT100 enhancements by Peter MacDonald. * * Copy and paste function by Andrew Haylett, * some enhancements by Alessandro Rubini. * * Code to check for different video-cards mostly by Galen Hunt, * * * Rudimentary ISO 10646/Unicode/UTF-8 character set support by * Markus Kuhn, . * * Dynamic allocation of consoles, aeb@cwi.nl, May 1994 * Resizing of consoles, aeb, 940926 * * Code for xterm like mouse click reporting by Peter Orbaek 20-Jul-94 * * * User-defined bell sound, new setterm control sequences and printk * redirection by Martin Mares 19-Nov-95 * * APM screenblank bug fixed Takashi Manabe * * Merge with the abstract console driver by Geert Uytterhoeven * , Jan 1997. * * Original m68k console driver modifications by * * - Arno Griffioen * - David Carter * * The abstract console driver provides a generic interface for a text * console. It supports VGA text mode, frame buffer based graphical consoles * and special graphics processors that are only accessible through some * registers (e.g. a TMS340x0 GSP). * * The interface to the hardware is specified using a special structure * (struct consw) which contains function pointers to console operations * (see for more information). * * Support for changeable cursor shape * by Pavel Machek , August 1997 * * Ported to i386 and con_scrolldelta fixed * by Emmanuel Marty , April 1998 * * Resurrected character buffers in videoram plus lots of other trickery * by Martin Mares , July 1998 * * Removed old-style timers, introduced console_timer, made timer * deletion SMP-safe. 17Jun00, Andrew Morton * * Removed console_lock, enabled interrupts across all console operations * 13 March 2001, Andrew Morton * * Fixed UTF-8 mode so alternate charset modes always work according * to control sequences interpreted in do_con_trol function * preserving backward VT100 semigraphics compatibility, * malformed UTF sequences represented as sequences of replacement glyphs, * original codes or '?' as a last resort if replacement glyph is undefined * by Adam Tla/lka , Aug 2006 */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define MAX_NR_CON_DRIVER 16 #define CON_DRIVER_FLAG_MODULE 1 #define CON_DRIVER_FLAG_INIT 2 #define CON_DRIVER_FLAG_ATTR 4 #define CON_DRIVER_FLAG_ZOMBIE 8 struct con_driver { const struct consw *con; const char *desc; struct device *dev; int node; int first; int last; int flag; }; static struct con_driver registered_con_driver[MAX_NR_CON_DRIVER]; const struct consw *conswitchp; /* * Here is the default bell parameters: 750HZ, 1/8th of a second */ #define DEFAULT_BELL_PITCH 750 #define DEFAULT_BELL_DURATION (HZ/8) #define DEFAULT_CURSOR_BLINK_MS 200 struct vc vc_cons [MAX_NR_CONSOLES]; EXPORT_SYMBOL(vc_cons); static const struct consw *con_driver_map[MAX_NR_CONSOLES]; static int con_open(struct tty_struct *, struct file *); static void vc_init(struct vc_data *vc, int do_clear); static void gotoxy(struct vc_data *vc, int new_x, int new_y); static void save_cur(struct vc_data *vc); static void reset_terminal(struct vc_data *vc, int do_clear); static void con_flush_chars(struct tty_struct *tty); static int set_vesa_blanking(char __user *p); static void set_cursor(struct vc_data *vc); static void hide_cursor(struct vc_data *vc); static void console_callback(struct work_struct *ignored); static void con_driver_unregister_callback(struct work_struct *ignored); static void blank_screen_t(struct timer_list *unused); static void set_palette(struct vc_data *vc); static void unblank_screen(void); #define vt_get_kmsg_redirect() vt_kmsg_redirect(-1) int default_utf8 = true; module_param(default_utf8, int, S_IRUGO | S_IWUSR); int global_cursor_default = -1; module_param(global_cursor_default, int, S_IRUGO | S_IWUSR); EXPORT_SYMBOL(global_cursor_default); static int cur_default = CUR_UNDERLINE; module_param(cur_default, int, S_IRUGO | S_IWUSR); /* * ignore_poke: don't unblank the screen when things are typed. This is * mainly for the privacy of braille terminal users. */ static int ignore_poke; int do_poke_blanked_console; int console_blanked; EXPORT_SYMBOL(console_blanked); static int vesa_blank_mode; /* 0:none 1:suspendV 2:suspendH 3:powerdown */ static int vesa_off_interval; static int blankinterval; core_param(consoleblank, blankinterval, int, 0444); static DECLARE_WORK(console_work, console_callback); static DECLARE_WORK(con_driver_unregister_work, con_driver_unregister_callback); /* * fg_console is the current virtual console, * last_console is the last used one, * want_console is the console we want to switch to, * saved_* variants are for save/restore around kernel debugger enter/leave */ int fg_console; EXPORT_SYMBOL(fg_console); int last_console; int want_console = -1; static int saved_fg_console; static int saved_last_console; static int saved_want_console; static int saved_vc_mode; static int saved_console_blanked; /* * For each existing display, we have a pointer to console currently visible * on that display, allowing consoles other than fg_console to be refreshed * appropriately. Unless the low-level driver supplies its own display_fg * variable, we use this one for the "master display". */ static struct vc_data *master_display_fg; /* * Unfortunately, we need to delay tty echo when we're currently writing to the * console since the code is (and always was) not re-entrant, so we schedule * all flip requests to process context with schedule-task() and run it from * console_callback(). */ /* * For the same reason, we defer scrollback to the console callback. */ static int scrollback_delta; /* * Hook so that the power management routines can (un)blank * the console on our behalf. */ int (*console_blank_hook)(int); EXPORT_SYMBOL(console_blank_hook); static DEFINE_TIMER(console_timer, blank_screen_t); static int blank_state; static int blank_timer_expired; enum { blank_off = 0, blank_normal_wait, blank_vesa_wait, }; /* * /sys/class/tty/tty0/ * * the attribute 'active' contains the name of the current vc * console and it supports poll() to detect vc switches */ static struct device *tty0dev; /* * Notifier list for console events. */ static ATOMIC_NOTIFIER_HEAD(vt_notifier_list); int register_vt_notifier(struct notifier_block *nb) { return atomic_notifier_chain_register(&vt_notifier_list, nb); } EXPORT_SYMBOL_GPL(register_vt_notifier); int unregister_vt_notifier(struct notifier_block *nb) { return atomic_notifier_chain_unregister(&vt_notifier_list, nb); } EXPORT_SYMBOL_GPL(unregister_vt_notifier); static void notify_write(struct vc_data *vc, unsigned int unicode) { struct vt_notifier_param param = { .vc = vc, .c = unicode }; atomic_notifier_call_chain(&vt_notifier_list, VT_WRITE, ¶m); } static void notify_update(struct vc_data *vc) { struct vt_notifier_param param = { .vc = vc }; atomic_notifier_call_chain(&vt_notifier_list, VT_UPDATE, ¶m); } /* * Low-Level Functions */ static inline bool con_is_fg(const struct vc_data *vc) { return vc->vc_num == fg_console; } static inline bool con_should_update(const struct vc_data *vc) { return con_is_visible(vc) && !console_blanked; } static inline unsigned short *screenpos(const struct vc_data *vc, int offset, bool viewed) { unsigned short *p; if (!viewed) p = (unsigned short *)(vc->vc_origin + offset); else if (!vc->vc_sw->con_screen_pos) p = (unsigned short *)(vc->vc_visible_origin + offset); else p = vc->vc_sw->con_screen_pos(vc, offset); return p; } /* Called from the keyboard irq path.. */ static inline void scrolldelta(int lines) { /* FIXME */ /* scrolldelta needs some kind of consistency lock, but the BKL was and still is not protecting versus the scheduled back end */ scrollback_delta += lines; schedule_console_callback(); } void schedule_console_callback(void) { schedule_work(&console_work); } /* * Code to manage unicode-based screen buffers */ /* * Our screen buffer is preceded by an array of line pointers so that * scrolling only implies some pointer shuffling. */ static u32 **vc_uniscr_alloc(unsigned int cols, unsigned int rows) { u32 **uni_lines; void *p; unsigned int memsize, i, col_size = cols * sizeof(**uni_lines); /* allocate everything in one go */ memsize = col_size * rows; memsize += rows * sizeof(*uni_lines); uni_lines = vzalloc(memsize); if (!uni_lines) return NULL; /* initial line pointers */ p = uni_lines + rows; for (i = 0; i < rows; i++) { uni_lines[i] = p; p += col_size; } return uni_lines; } static void vc_uniscr_free(u32 **uni_lines) { vfree(uni_lines); } static void vc_uniscr_set(struct vc_data *vc, u32 **new_uni_lines) { vc_uniscr_free(vc->vc_uni_lines); vc->vc_uni_lines = new_uni_lines; } static void vc_uniscr_putc(struct vc_data *vc, u32 uc) { if (vc->vc_uni_lines) vc->vc_uni_lines[vc->state.y][vc->state.x] = uc; } static void vc_uniscr_insert(struct vc_data *vc, unsigned int nr) { if (vc->vc_uni_lines) { u32 *ln = vc->vc_uni_lines[vc->state.y]; unsigned int x = vc->state.x, cols = vc->vc_cols; memmove(&ln[x + nr], &ln[x], (cols - x - nr) * sizeof(*ln)); memset32(&ln[x], ' ', nr); } } static void vc_uniscr_delete(struct vc_data *vc, unsigned int nr) { if (vc->vc_uni_lines) { u32 *ln = vc->vc_uni_lines[vc->state.y]; unsigned int x = vc->state.x, cols = vc->vc_cols; memmove(&ln[x], &ln[x + nr], (cols - x - nr) * sizeof(*ln)); memset32(&ln[cols - nr], ' ', nr); } } static void vc_uniscr_clear_line(struct vc_data *vc, unsigned int x, unsigned int nr) { if (vc->vc_uni_lines) memset32(&vc->vc_uni_lines[vc->state.y][x], ' ', nr); } static void vc_uniscr_clear_lines(struct vc_data *vc, unsigned int y, unsigned int nr) { if (vc->vc_uni_lines) while (nr--) memset32(vc->vc_uni_lines[y++], ' ', vc->vc_cols); } /* juggling array rotation algorithm (complexity O(N), size complexity O(1)) */ static void juggle_array(u32 **array, unsigned int size, unsigned int nr) { unsigned int gcd_idx; for (gcd_idx = 0; gcd_idx < gcd(nr, size); gcd_idx++) { u32 *gcd_idx_val = array[gcd_idx]; unsigned int dst_idx = gcd_idx; while (1) { unsigned int src_idx = (dst_idx + nr) % size; if (src_idx == gcd_idx) break; array[dst_idx] = array[src_idx]; dst_idx = src_idx; } array[dst_idx] = gcd_idx_val; } } static void vc_uniscr_scroll(struct vc_data *vc, unsigned int top, unsigned int bottom, enum con_scroll dir, unsigned int nr) { u32 **uni_lines = vc->vc_uni_lines; unsigned int size = bottom - top; if (!uni_lines) return; if (dir == SM_DOWN) { juggle_array(&uni_lines[top], size, size - nr); vc_uniscr_clear_lines(vc, top, nr); } else { juggle_array(&uni_lines[top], size, nr); vc_uniscr_clear_lines(vc, bottom - nr, nr); } } static void vc_uniscr_copy_area(u32 **dst_lines, unsigned int dst_cols, unsigned int dst_rows, u32 **src_lines, unsigned int src_cols, unsigned int src_top_row, unsigned int src_bot_row) { unsigned int dst_row = 0; if (!dst_lines) return; while (src_top_row < src_bot_row) { u32 *src_line = src_lines[src_top_row]; u32 *dst_line = dst_lines[dst_row]; memcpy(dst_line, src_line, src_cols * sizeof(*src_line)); if (dst_cols - src_cols) memset32(dst_line + src_cols, ' ', dst_cols - src_cols); src_top_row++; dst_row++; } while (dst_row < dst_rows) { u32 *dst_line = dst_lines[dst_row]; memset32(dst_line, ' ', dst_cols); dst_row++; } } /* * Called from vcs_read() to make sure unicode screen retrieval is possible. * This will initialize the unicode screen buffer if not already done. * This returns 0 if OK, or a negative error code otherwise. * In particular, -ENODATA is returned if the console is not in UTF-8 mode. */ int vc_uniscr_check(struct vc_data *vc) { u32 **uni_lines; unsigned short *p; int x, y, mask; WARN_CONSOLE_UNLOCKED(); if (!vc->vc_utf) return -ENODATA; if (vc->vc_uni_lines) return 0; uni_lines = vc_uniscr_alloc(vc->vc_cols, vc->vc_rows); if (!uni_lines) return -ENOMEM; /* * Let's populate it initially with (imperfect) reverse translation. * This is the next best thing we can do short of having it enabled * from the start even when no users rely on this functionality. True * unicode content will be available after a complete screen refresh. */ p = (unsigned short *)vc->vc_origin; mask = vc->vc_hi_font_mask | 0xff; for (y = 0; y < vc->vc_rows; y++) { u32 *line = uni_lines[y]; for (x = 0; x < vc->vc_cols; x++) { u16 glyph = scr_readw(p++) & mask; line[x] = inverse_translate(vc, glyph, true); } } vc->vc_uni_lines = uni_lines; return 0; } /* * Called from vcs_read() to get the unicode data from the screen. * This must be preceded by a successful call to vc_uniscr_check() once * the console lock has been taken. */ void vc_uniscr_copy_line(const struct vc_data *vc, void *dest, bool viewed, unsigned int row, unsigned int col, unsigned int nr) { u32 **uni_lines = vc->vc_uni_lines; int offset = row * vc->vc_size_row + col * 2; unsigned long pos; if (WARN_ON_ONCE(!uni_lines)) return; pos = (unsigned long)screenpos(vc, offset, viewed); if (pos >= vc->vc_origin && pos < vc->vc_scr_end) { /* * Desired position falls in the main screen buffer. * However the actual row/col might be different if * scrollback is active. */ row = (pos - vc->vc_origin) / vc->vc_size_row; col = ((pos - vc->vc_origin) % vc->vc_size_row) / 2; memcpy(dest, &uni_lines[row][col], nr * sizeof(u32)); } else { /* * Scrollback is active. For now let's simply backtranslate * the screen glyphs until the unicode screen buffer does * synchronize with console display drivers for a scrollback * buffer of its own. */ u16 *p = (u16 *)pos; int mask = vc->vc_hi_font_mask | 0xff; u32 *uni_buf = dest; while (nr--) { u16 glyph = scr_readw(p++) & mask; *uni_buf++ = inverse_translate(vc, glyph, true); } } } static void con_scroll(struct vc_data *vc, unsigned int top, unsigned int bottom, enum con_scroll dir, unsigned int nr) { unsigned int rows = bottom - top; u16 *clear, *dst, *src; if (top + nr >= bottom) nr = rows - 1; if (bottom > vc->vc_rows || top >= bottom || nr < 1) return; vc_uniscr_scroll(vc, top, bottom, dir, nr); if (con_is_visible(vc) && vc->vc_sw->con_scroll(vc, top, bottom, dir, nr)) return; src = clear = (u16 *)(vc->vc_origin + vc->vc_size_row * top); dst = (u16 *)(vc->vc_origin + vc->vc_size_row * (top + nr)); if (dir == SM_UP) { clear = src + (rows - nr) * vc->vc_cols; swap(src, dst); } scr_memmovew(dst, src, (rows - nr) * vc->vc_size_row); scr_memsetw(clear, vc->vc_video_erase_char, vc->vc_size_row * nr); } static void do_update_region(struct vc_data *vc, unsigned long start, int count) { unsigned int xx, yy, offset; u16 *p; p = (u16 *) start; if (!vc->vc_sw->con_getxy) { offset = (start - vc->vc_origin) / 2; xx = offset % vc->vc_cols; yy = offset / vc->vc_cols; } else { int nxx, nyy; start = vc->vc_sw->con_getxy(vc, start, &nxx, &nyy); xx = nxx; yy = nyy; } for(;;) { u16 attrib = scr_readw(p) & 0xff00; int startx = xx; u16 *q = p; while (xx < vc->vc_cols && count) { if (attrib != (scr_readw(p) & 0xff00)) { if (p > q) vc->vc_sw->con_putcs(vc, q, p-q, yy, startx); startx = xx; q = p; attrib = scr_readw(p) & 0xff00; } p++; xx++; count--; } if (p > q) vc->vc_sw->con_putcs(vc, q, p-q, yy, startx); if (!count) break; xx = 0; yy++; if (vc->vc_sw->con_getxy) { p = (u16 *)start; start = vc->vc_sw->con_getxy(vc, start, NULL, NULL); } } } void update_region(struct vc_data *vc, unsigned long start, int count) { WARN_CONSOLE_UNLOCKED(); if (con_should_update(vc)) { hide_cursor(vc); do_update_region(vc, start, count); set_cursor(vc); } } EXPORT_SYMBOL(update_region); /* Structure of attributes is hardware-dependent */ static u8 build_attr(struct vc_data *vc, u8 _color, enum vc_intensity _intensity, bool _blink, bool _underline, bool _reverse, bool _italic) { if (vc->vc_sw->con_build_attr) return vc->vc_sw->con_build_attr(vc, _color, _intensity, _blink, _underline, _reverse, _italic); /* * ++roman: I completely changed the attribute format for monochrome * mode (!can_do_color). The formerly used MDA (monochrome display * adapter) format didn't allow the combination of certain effects. * Now the attribute is just a bit vector: * Bit 0..1: intensity (0..2) * Bit 2 : underline * Bit 3 : reverse * Bit 7 : blink */ { u8 a = _color; if (!vc->vc_can_do_color) return _intensity | (_italic << 1) | (_underline << 2) | (_reverse << 3) | (_blink << 7); if (_italic) a = (a & 0xF0) | vc->vc_itcolor; else if (_underline) a = (a & 0xf0) | vc->vc_ulcolor; else if (_intensity == VCI_HALF_BRIGHT) a = (a & 0xf0) | vc->vc_halfcolor; if (_reverse) a = (a & 0x88) | (((a >> 4) | (a << 4)) & 0x77); if (_blink) a ^= 0x80; if (_intensity == VCI_BOLD) a ^= 0x08; if (vc->vc_hi_font_mask == 0x100) a <<= 1; return a; } } static void update_attr(struct vc_data *vc) { vc->vc_attr = build_attr(vc, vc->state.color, vc->state.intensity, vc->state.blink, vc->state.underline, vc->state.reverse ^ vc->vc_decscnm, vc->state.italic); vc->vc_video_erase_char = ' ' | (build_attr(vc, vc->state.color, VCI_NORMAL, vc->state.blink, false, vc->vc_decscnm, false) << 8); } /* Note: inverting the screen twice should revert to the original state */ void invert_screen(struct vc_data *vc, int offset, int count, bool viewed) { unsigned short *p; WARN_CONSOLE_UNLOCKED(); count /= 2; p = screenpos(vc, offset, viewed); if (vc->vc_sw->con_invert_region) { vc->vc_sw->con_invert_region(vc, p, count); } else { u16 *q = p; int cnt = count; u16 a; if (!vc->vc_can_do_color) { while (cnt--) { a = scr_readw(q); a ^= 0x0800; scr_writew(a, q); q++; } } else if (vc->vc_hi_font_mask == 0x100) { while (cnt--) { a = scr_readw(q); a = (a & 0x11ff) | ((a & 0xe000) >> 4) | ((a & 0x0e00) << 4); scr_writew(a, q); q++; } } else { while (cnt--) { a = scr_readw(q); a = (a & 0x88ff) | ((a & 0x7000) >> 4) | ((a & 0x0700) << 4); scr_writew(a, q); q++; } } } if (con_should_update(vc)) do_update_region(vc, (unsigned long) p, count); notify_update(vc); } /* used by selection: complement pointer position */ void complement_pos(struct vc_data *vc, int offset) { static int old_offset = -1; static unsigned short old; static unsigned short oldx, oldy; WARN_CONSOLE_UNLOCKED(); if (old_offset != -1 && old_offset >= 0 && old_offset < vc->vc_screenbuf_size) { scr_writew(old, screenpos(vc, old_offset, true)); if (con_should_update(vc)) vc->vc_sw->con_putc(vc, old, oldy, oldx); notify_update(vc); } old_offset = offset; if (offset != -1 && offset >= 0 && offset < vc->vc_screenbuf_size) { unsigned short new; unsigned short *p; p = screenpos(vc, offset, true); old = scr_readw(p); new = old ^ vc->vc_complement_mask; scr_writew(new, p); if (con_should_update(vc)) { oldx = (offset >> 1) % vc->vc_cols; oldy = (offset >> 1) / vc->vc_cols; vc->vc_sw->con_putc(vc, new, oldy, oldx); } notify_update(vc); } } static void insert_char(struct vc_data *vc, unsigned int nr) { unsigned short *p = (unsigned short *) vc->vc_pos; vc_uniscr_insert(vc, nr); scr_memmovew(p + nr, p, (vc->vc_cols - vc->state.x - nr) * 2); scr_memsetw(p, vc->vc_video_erase_char, nr * 2); vc->vc_need_wrap = 0; if (con_should_update(vc)) do_update_region(vc, (unsigned long) p, vc->vc_cols - vc->state.x); } static void delete_char(struct vc_data *vc, unsigned int nr) { unsigned short *p = (unsigned short *) vc->vc_pos; vc_uniscr_delete(vc, nr); scr_memmovew(p, p + nr, (vc->vc_cols - vc->state.x - nr) * 2); scr_memsetw(p + vc->vc_cols - vc->state.x - nr, vc->vc_video_erase_char, nr * 2); vc->vc_need_wrap = 0; if (con_should_update(vc)) do_update_region(vc, (unsigned long) p, vc->vc_cols - vc->state.x); } static int softcursor_original = -1; static void add_softcursor(struct vc_data *vc) { int i = scr_readw((u16 *) vc->vc_pos); u32 type = vc->vc_cursor_type; if (!(type & CUR_SW)) return; if (softcursor_original != -1) return; softcursor_original = i; i |= CUR_SET(type); i ^= CUR_CHANGE(type); if ((type & CUR_ALWAYS_BG) && (softcursor_original & CUR_BG) == (i & CUR_BG)) i ^= CUR_BG; if ((type & CUR_INVERT_FG_BG) && (i & CUR_FG) == ((i & CUR_BG) >> 4)) i ^= CUR_FG; scr_writew(i, (u16 *)vc->vc_pos); if (con_should_update(vc)) vc->vc_sw->con_putc(vc, i, vc->state.y, vc->state.x); } static void hide_softcursor(struct vc_data *vc) { if (softcursor_original != -1) { scr_writew(softcursor_original, (u16 *)vc->vc_pos); if (con_should_update(vc)) vc->vc_sw->con_putc(vc, softcursor_original, vc->state.y, vc->state.x); softcursor_original = -1; } } static void hide_cursor(struct vc_data *vc) { if (vc_is_sel(vc)) clear_selection(); vc->vc_sw->con_cursor(vc, CM_ERASE); hide_softcursor(vc); } static void set_cursor(struct vc_data *vc) { if (!con_is_fg(vc) || console_blanked || vc->vc_mode == KD_GRAPHICS) return; if (vc->vc_deccm) { if (vc_is_sel(vc)) clear_selection(); add_softcursor(vc); if (CUR_SIZE(vc->vc_cursor_type) != CUR_NONE) vc->vc_sw->con_cursor(vc, CM_DRAW); } else hide_cursor(vc); } static void set_origin(struct vc_data *vc) { WARN_CONSOLE_UNLOCKED(); if (!con_is_visible(vc) || !vc->vc_sw->con_set_origin || !vc->vc_sw->con_set_origin(vc)) vc->vc_origin = (unsigned long)vc->vc_screenbuf; vc->vc_visible_origin = vc->vc_origin; vc->vc_scr_end = vc->vc_origin + vc->vc_screenbuf_size; vc->vc_pos = vc->vc_origin + vc->vc_size_row * vc->state.y + 2 * vc->state.x; } static void save_screen(struct vc_data *vc) { WARN_CONSOLE_UNLOCKED(); if (vc->vc_sw->con_save_screen) vc->vc_sw->con_save_screen(vc); } static void flush_scrollback(struct vc_data *vc) { WARN_CONSOLE_UNLOCKED(); set_origin(vc); if (vc->vc_sw->con_flush_scrollback) { vc->vc_sw->con_flush_scrollback(vc); } else if (con_is_visible(vc)) { /* * When no con_flush_scrollback method is provided then the * legacy way for flushing the scrollback buffer is to use * a side effect of the con_switch method. We do it only on * the foreground console as background consoles have no * scrollback buffers in that case and we obviously don't * want to switch to them. */ hide_cursor(vc); vc->vc_sw->con_switch(vc); set_cursor(vc); } } /* * Redrawing of screen */ void clear_buffer_attributes(struct vc_data *vc) { unsigned short *p = (unsigned short *)vc->vc_origin; int count = vc->vc_screenbuf_size / 2; int mask = vc->vc_hi_font_mask | 0xff; for (; count > 0; count--, p++) { scr_writew((scr_readw(p)&mask) | (vc->vc_video_erase_char & ~mask), p); } } void redraw_screen(struct vc_data *vc, int is_switch) { int redraw = 0; WARN_CONSOLE_UNLOCKED(); if (!vc) { /* strange ... */ /* printk("redraw_screen: tty %d not allocated ??\n", new_console+1); */ return; } if (is_switch) { struct vc_data *old_vc = vc_cons[fg_console].d; if (old_vc == vc) return; if (!con_is_visible(vc)) redraw = 1; *vc->vc_display_fg = vc; fg_console = vc->vc_num; hide_cursor(old_vc); if (!con_is_visible(old_vc)) { save_screen(old_vc); set_origin(old_vc); } if (tty0dev) sysfs_notify(&tty0dev->kobj, NULL, "active"); } else { hide_cursor(vc); redraw = 1; } if (redraw) { int update; int old_was_color = vc->vc_can_do_color; set_origin(vc); update = vc->vc_sw->con_switch(vc); set_palette(vc); /* * If console changed from mono<->color, the best we can do * is to clear the buffer attributes. As it currently stands, * rebuilding new attributes from the old buffer is not doable * without overly complex code. */ if (old_was_color != vc->vc_can_do_color) { update_attr(vc); clear_buffer_attributes(vc); } if (update && vc->vc_mode != KD_GRAPHICS) do_update_region(vc, vc->vc_origin, vc->vc_screenbuf_size / 2); } set_cursor(vc); if (is_switch) { vt_set_leds_compute_shiftstate(); notify_update(vc); } } EXPORT_SYMBOL(redraw_screen); /* * Allocation, freeing and resizing of VTs. */ int vc_cons_allocated(unsigned int i) { return (i < MAX_NR_CONSOLES && vc_cons[i].d); } static void visual_init(struct vc_data *vc, int num, int init) { /* ++Geert: vc->vc_sw->con_init determines console size */ if (vc->vc_sw) module_put(vc->vc_sw->owner); vc->vc_sw = conswitchp; if (con_driver_map[num]) vc->vc_sw = con_driver_map[num]; __module_get(vc->vc_sw->owner); vc->vc_num = num; vc->vc_display_fg = &master_display_fg; if (vc->uni_pagedict_loc) con_free_unimap(vc); vc->uni_pagedict_loc = &vc->uni_pagedict; vc->uni_pagedict = NULL; vc->vc_hi_font_mask = 0; vc->vc_complement_mask = 0; vc->vc_can_do_color = 0; vc->vc_cur_blink_ms = DEFAULT_CURSOR_BLINK_MS; vc->vc_sw->con_init(vc, init); if (!vc->vc_complement_mask) vc->vc_complement_mask = vc->vc_can_do_color ? 0x7700 : 0x0800; vc->vc_s_complement_mask = vc->vc_complement_mask; vc->vc_size_row = vc->vc_cols << 1; vc->vc_screenbuf_size = vc->vc_rows * vc->vc_size_row; } static void visual_deinit(struct vc_data *vc) { vc->vc_sw->con_deinit(vc); module_put(vc->vc_sw->owner); } static void vc_port_destruct(struct tty_port *port) { struct vc_data *vc = container_of(port, struct vc_data, port); kfree(vc); } static const struct tty_port_operations vc_port_ops = { .destruct = vc_port_destruct, }; /* * Change # of rows and columns (0 means unchanged/the size of fg_console) * [this is to be used together with some user program * like resize that changes the hardware videomode] */ #define VC_MAXCOL (32767) #define VC_MAXROW (32767) int vc_allocate(unsigned int currcons) /* return 0 on success */ { struct vt_notifier_param param; struct vc_data *vc; int err; WARN_CONSOLE_UNLOCKED(); if (currcons >= MAX_NR_CONSOLES) return -ENXIO; if (vc_cons[currcons].d) return 0; /* due to the granularity of kmalloc, we waste some memory here */ /* the alloc is done in two steps, to optimize the common situation of a 25x80 console (structsize=216, screenbuf_size=4000) */ /* although the numbers above are not valid since long ago, the point is still up-to-date and the comment still has its value even if only as a historical artifact. --mj, July 1998 */ param.vc = vc = kzalloc(sizeof(struct vc_data), GFP_KERNEL); if (!vc) return -ENOMEM; vc_cons[currcons].d = vc; tty_port_init(&vc->port); vc->port.ops = &vc_port_ops; INIT_WORK(&vc_cons[currcons].SAK_work, vc_SAK); visual_init(vc, currcons, 1); if (!*vc->uni_pagedict_loc) con_set_default_unimap(vc); err = -EINVAL; if (vc->vc_cols > VC_MAXCOL || vc->vc_rows > VC_MAXROW || vc->vc_screenbuf_size > KMALLOC_MAX_SIZE || !vc->vc_screenbuf_size) goto err_free; err = -ENOMEM; vc->vc_screenbuf = kzalloc(vc->vc_screenbuf_size, GFP_KERNEL); if (!vc->vc_screenbuf) goto err_free; /* If no drivers have overridden us and the user didn't pass a boot option, default to displaying the cursor */ if (global_cursor_default == -1) global_cursor_default = 1; vc_init(vc, 1); vcs_make_sysfs(currcons); atomic_notifier_call_chain(&vt_notifier_list, VT_ALLOCATE, ¶m); return 0; err_free: visual_deinit(vc); kfree(vc); vc_cons[currcons].d = NULL; return err; } static inline int resize_screen(struct vc_data *vc, int width, int height, int user) { /* Resizes the resolution of the display adapater */ int err = 0; if (vc->vc_sw->con_resize) err = vc->vc_sw->con_resize(vc, width, height, user); return err; } /** * vc_do_resize - resizing method for the tty * @tty: tty being resized * @vc: virtual console private data * @cols: columns * @lines: lines * * Resize a virtual console, clipping according to the actual constraints. * If the caller passes a tty structure then update the termios winsize * information and perform any necessary signal handling. * * Caller must hold the console semaphore. Takes the termios rwsem and * ctrl.lock of the tty IFF a tty is passed. */ static int vc_do_resize(struct tty_struct *tty, struct vc_data *vc, unsigned int cols, unsigned int lines) { unsigned long old_origin, new_origin, new_scr_end, rlth, rrem, err = 0; unsigned long end; unsigned int old_rows, old_row_size, first_copied_row; unsigned int new_cols, new_rows, new_row_size, new_screen_size; unsigned int user; unsigned short *oldscreen, *newscreen; u32 **new_uniscr = NULL; WARN_CONSOLE_UNLOCKED(); if (!vc) return -ENXIO; user = vc->vc_resize_user; vc->vc_resize_user = 0; if (cols > VC_MAXCOL || lines > VC_MAXROW) return -EINVAL; new_cols = (cols ? cols : vc->vc_cols); new_rows = (lines ? lines : vc->vc_rows); new_row_size = new_cols << 1; new_screen_size = new_row_size * new_rows; if (new_cols == vc->vc_cols && new_rows == vc->vc_rows) { /* * This function is being called here to cover the case * where the userspace calls the FBIOPUT_VSCREENINFO twice, * passing the same fb_var_screeninfo containing the fields * yres/xres equal to a number non-multiple of vc_font.height * and yres_virtual/xres_virtual equal to number lesser than the * vc_font.height and yres/xres. * In the second call, the struct fb_var_screeninfo isn't * being modified by the underlying driver because of the * if above, and this causes the fbcon_display->vrows to become * negative and it eventually leads to out-of-bound * access by the imageblit function. * To give the correct values to the struct and to not have * to deal with possible errors from the code below, we call * the resize_screen here as well. */ return resize_screen(vc, new_cols, new_rows, user); } if (new_screen_size > KMALLOC_MAX_SIZE || !new_screen_size) return -EINVAL; newscreen = kzalloc(new_screen_size, GFP_USER); if (!newscreen) return -ENOMEM; if (vc->vc_uni_lines) { new_uniscr = vc_uniscr_alloc(new_cols, new_rows); if (!new_uniscr) { kfree(newscreen); return -ENOMEM; } } if (vc_is_sel(vc)) clear_selection(); old_rows = vc->vc_rows; old_row_size = vc->vc_size_row; err = resize_screen(vc, new_cols, new_rows, user); if (err) { kfree(newscreen); vc_uniscr_free(new_uniscr); return err; } vc->vc_rows = new_rows; vc->vc_cols = new_cols; vc->vc_size_row = new_row_size; vc->vc_screenbuf_size = new_screen_size; rlth = min(old_row_size, new_row_size); rrem = new_row_size - rlth; old_origin = vc->vc_origin; new_origin = (long) newscreen; new_scr_end = new_origin + new_screen_size; if (vc->state.y > new_rows) { if (old_rows - vc->state.y < new_rows) { /* * Cursor near the bottom, copy contents from the * bottom of buffer */ first_copied_row = (old_rows - new_rows); } else { /* * Cursor is in no man's land, copy 1/2 screenful * from the top and bottom of cursor position */ first_copied_row = (vc->state.y - new_rows/2); } old_origin += first_copied_row * old_row_size; } else first_copied_row = 0; end = old_origin + old_row_size * min(old_rows, new_rows); vc_uniscr_copy_area(new_uniscr, new_cols, new_rows, vc->vc_uni_lines, rlth/2, first_copied_row, min(old_rows, new_rows)); vc_uniscr_set(vc, new_uniscr); update_attr(vc); while (old_origin < end) { scr_memcpyw((unsigned short *) new_origin, (unsigned short *) old_origin, rlth); if (rrem) scr_memsetw((void *)(new_origin + rlth), vc->vc_video_erase_char, rrem); old_origin += old_row_size; new_origin += new_row_size; } if (new_scr_end > new_origin) scr_memsetw((void *)new_origin, vc->vc_video_erase_char, new_scr_end - new_origin); oldscreen = vc->vc_screenbuf; vc->vc_screenbuf = newscreen; vc->vc_screenbuf_size = new_screen_size; set_origin(vc); kfree(oldscreen); /* do part of a reset_terminal() */ vc->vc_top = 0; vc->vc_bottom = vc->vc_rows; gotoxy(vc, vc->state.x, vc->state.y); save_cur(vc); if (tty) { /* Rewrite the requested winsize data with the actual resulting sizes */ struct winsize ws; memset(&ws, 0, sizeof(ws)); ws.ws_row = vc->vc_rows; ws.ws_col = vc->vc_cols; ws.ws_ypixel = vc->vc_scan_lines; tty_do_resize(tty, &ws); } if (con_is_visible(vc)) update_screen(vc); vt_event_post(VT_EVENT_RESIZE, vc->vc_num, vc->vc_num); notify_update(vc); return err; } /** * vc_resize - resize a VT * @vc: virtual console * @cols: columns * @rows: rows * * Resize a virtual console as seen from the console end of things. We * use the common vc_do_resize methods to update the structures. The * caller must hold the console sem to protect console internals and * vc->port.tty */ int vc_resize(struct vc_data *vc, unsigned int cols, unsigned int rows) { return vc_do_resize(vc->port.tty, vc, cols, rows); } EXPORT_SYMBOL(vc_resize); /** * vt_resize - resize a VT * @tty: tty to resize * @ws: winsize attributes * * Resize a virtual terminal. This is called by the tty layer as we * register our own handler for resizing. The mutual helper does all * the actual work. * * Takes the console sem and the called methods then take the tty * termios_rwsem and the tty ctrl.lock in that order. */ static int vt_resize(struct tty_struct *tty, struct winsize *ws) { struct vc_data *vc = tty->driver_data; int ret; console_lock(); ret = vc_do_resize(tty, vc, ws->ws_col, ws->ws_row); console_unlock(); return ret; } struct vc_data *vc_deallocate(unsigned int currcons) { struct vc_data *vc = NULL; WARN_CONSOLE_UNLOCKED(); if (vc_cons_allocated(currcons)) { struct vt_notifier_param param; param.vc = vc = vc_cons[currcons].d; atomic_notifier_call_chain(&vt_notifier_list, VT_DEALLOCATE, ¶m); vcs_remove_sysfs(currcons); visual_deinit(vc); con_free_unimap(vc); put_pid(vc->vt_pid); vc_uniscr_set(vc, NULL); kfree(vc->vc_screenbuf); vc_cons[currcons].d = NULL; } return vc; } /* * VT102 emulator */ enum { EPecma = 0, EPdec, EPeq, EPgt, EPlt}; #define set_kbd(vc, x) vt_set_kbd_mode_bit((vc)->vc_num, (x)) #define clr_kbd(vc, x) vt_clr_kbd_mode_bit((vc)->vc_num, (x)) #define is_kbd(vc, x) vt_get_kbd_mode_bit((vc)->vc_num, (x)) #define decarm VC_REPEAT #define decckm VC_CKMODE #define kbdapplic VC_APPLIC #define lnm VC_CRLF const unsigned char color_table[] = { 0, 4, 2, 6, 1, 5, 3, 7, 8,12,10,14, 9,13,11,15 }; EXPORT_SYMBOL(color_table); /* the default colour table, for VGA+ colour systems */ unsigned char default_red[] = { 0x00, 0xaa, 0x00, 0xaa, 0x00, 0xaa, 0x00, 0xaa, 0x55, 0xff, 0x55, 0xff, 0x55, 0xff, 0x55, 0xff }; module_param_array(default_red, byte, NULL, S_IRUGO | S_IWUSR); EXPORT_SYMBOL(default_red); unsigned char default_grn[] = { 0x00, 0x00, 0xaa, 0x55, 0x00, 0x00, 0xaa, 0xaa, 0x55, 0x55, 0xff, 0xff, 0x55, 0x55, 0xff, 0xff }; module_param_array(default_grn, byte, NULL, S_IRUGO | S_IWUSR); EXPORT_SYMBOL(default_grn); unsigned char default_blu[] = { 0x00, 0x00, 0x00, 0x00, 0xaa, 0xaa, 0xaa, 0xaa, 0x55, 0x55, 0x55, 0x55, 0xff, 0xff, 0xff, 0xff }; module_param_array(default_blu, byte, NULL, S_IRUGO | S_IWUSR); EXPORT_SYMBOL(default_blu); /* * gotoxy() must verify all boundaries, because the arguments * might also be negative. If the given position is out of * bounds, the cursor is placed at the nearest margin. */ static void gotoxy(struct vc_data *vc, int new_x, int new_y) { int min_y, max_y; if (new_x < 0) vc->state.x = 0; else { if (new_x >= vc->vc_cols) vc->state.x = vc->vc_cols - 1; else vc->state.x = new_x; } if (vc->vc_decom) { min_y = vc->vc_top; max_y = vc->vc_bottom; } else { min_y = 0; max_y = vc->vc_rows; } if (new_y < min_y) vc->state.y = min_y; else if (new_y >= max_y) vc->state.y = max_y - 1; else vc->state.y = new_y; vc->vc_pos = vc->vc_origin + vc->state.y * vc->vc_size_row + (vc->state.x << 1); vc->vc_need_wrap = 0; } /* for absolute user moves, when decom is set */ static void gotoxay(struct vc_data *vc, int new_x, int new_y) { gotoxy(vc, new_x, vc->vc_decom ? (vc->vc_top + new_y) : new_y); } void scrollback(struct vc_data *vc) { scrolldelta(-(vc->vc_rows / 2)); } void scrollfront(struct vc_data *vc, int lines) { if (!lines) lines = vc->vc_rows / 2; scrolldelta(lines); } static void lf(struct vc_data *vc) { /* don't scroll if above bottom of scrolling region, or * if below scrolling region */ if (vc->state.y + 1 == vc->vc_bottom) con_scroll(vc, vc->vc_top, vc->vc_bottom, SM_UP, 1); else if (vc->state.y < vc->vc_rows - 1) { vc->state.y++; vc->vc_pos += vc->vc_size_row; } vc->vc_need_wrap = 0; notify_write(vc, '\n'); } static void ri(struct vc_data *vc) { /* don't scroll if below top of scrolling region, or * if above scrolling region */ if (vc->state.y == vc->vc_top) con_scroll(vc, vc->vc_top, vc->vc_bottom, SM_DOWN, 1); else if (vc->state.y > 0) { vc->state.y--; vc->vc_pos -= vc->vc_size_row; } vc->vc_need_wrap = 0; } static inline void cr(struct vc_data *vc) { vc->vc_pos -= vc->state.x << 1; vc->vc_need_wrap = vc->state.x = 0; notify_write(vc, '\r'); } static inline void bs(struct vc_data *vc) { if (vc->state.x) { vc->vc_pos -= 2; vc->state.x--; vc->vc_need_wrap = 0; notify_write(vc, '\b'); } } static inline void del(struct vc_data *vc) { /* ignored */ } static void csi_J(struct vc_data *vc, int vpar) { unsigned int count; unsigned short * start; switch (vpar) { case 0: /* erase from cursor to end of display */ vc_uniscr_clear_line(vc, vc->state.x, vc->vc_cols - vc->state.x); vc_uniscr_clear_lines(vc, vc->state.y + 1, vc->vc_rows - vc->state.y - 1); count = (vc->vc_scr_end - vc->vc_pos) >> 1; start = (unsigned short *)vc->vc_pos; break; case 1: /* erase from start to cursor */ vc_uniscr_clear_line(vc, 0, vc->state.x + 1); vc_uniscr_clear_lines(vc, 0, vc->state.y); count = ((vc->vc_pos - vc->vc_origin) >> 1) + 1; start = (unsigned short *)vc->vc_origin; break; case 3: /* include scrollback */ flush_scrollback(vc); fallthrough; case 2: /* erase whole display */ vc_uniscr_clear_lines(vc, 0, vc->vc_rows); count = vc->vc_cols * vc->vc_rows; start = (unsigned short *)vc->vc_origin; break; default: return; } scr_memsetw(start, vc->vc_video_erase_char, 2 * count); if (con_should_update(vc)) do_update_region(vc, (unsigned long) start, count); vc->vc_need_wrap = 0; } static void csi_K(struct vc_data *vc, int vpar) { unsigned int count; unsigned short *start = (unsigned short *)vc->vc_pos; int offset; switch (vpar) { case 0: /* erase from cursor to end of line */ offset = 0; count = vc->vc_cols - vc->state.x; break; case 1: /* erase from start of line to cursor */ offset = -vc->state.x; count = vc->state.x + 1; break; case 2: /* erase whole line */ offset = -vc->state.x; count = vc->vc_cols; break; default: return; } vc_uniscr_clear_line(vc, vc->state.x + offset, count); scr_memsetw(start + offset, vc->vc_video_erase_char, 2 * count); vc->vc_need_wrap = 0; if (con_should_update(vc)) do_update_region(vc, (unsigned long)(start + offset), count); } /* erase the following vpar positions */ static void csi_X(struct vc_data *vc, unsigned int vpar) { /* not vt100? */ unsigned int count; if (!vpar) vpar++; count = min(vpar, vc->vc_cols - vc->state.x); vc_uniscr_clear_line(vc, vc->state.x, count); scr_memsetw((unsigned short *)vc->vc_pos, vc->vc_video_erase_char, 2 * count); if (con_should_update(vc)) vc->vc_sw->con_clear(vc, vc->state.y, vc->state.x, 1, count); vc->vc_need_wrap = 0; } static void default_attr(struct vc_data *vc) { vc->state.intensity = VCI_NORMAL; vc->state.italic = false; vc->state.underline = false; vc->state.reverse = false; vc->state.blink = false; vc->state.color = vc->vc_def_color; } struct rgb { u8 r; u8 g; u8 b; }; static void rgb_from_256(int i, struct rgb *c) { if (i < 8) { /* Standard colours. */ c->r = i&1 ? 0xaa : 0x00; c->g = i&2 ? 0xaa : 0x00; c->b = i&4 ? 0xaa : 0x00; } else if (i < 16) { c->r = i&1 ? 0xff : 0x55; c->g = i&2 ? 0xff : 0x55; c->b = i&4 ? 0xff : 0x55; } else if (i < 232) { /* 6x6x6 colour cube. */ c->r = (i - 16) / 36 * 85 / 2; c->g = (i - 16) / 6 % 6 * 85 / 2; c->b = (i - 16) % 6 * 85 / 2; } else /* Grayscale ramp. */ c->r = c->g = c->b = i * 10 - 2312; } static void rgb_foreground(struct vc_data *vc, const struct rgb *c) { u8 hue = 0, max = max3(c->r, c->g, c->b); if (c->r > max / 2) hue |= 4; if (c->g > max / 2) hue |= 2; if (c->b > max / 2) hue |= 1; if (hue == 7 && max <= 0x55) { hue = 0; vc->state.intensity = VCI_BOLD; } else if (max > 0xaa) vc->state.intensity = VCI_BOLD; else vc->state.intensity = VCI_NORMAL; vc->state.color = (vc->state.color & 0xf0) | hue; } static void rgb_background(struct vc_data *vc, const struct rgb *c) { /* For backgrounds, err on the dark side. */ vc->state.color = (vc->state.color & 0x0f) | (c->r&0x80) >> 1 | (c->g&0x80) >> 2 | (c->b&0x80) >> 3; } /* * ITU T.416 Higher colour modes. They break the usual properties of SGR codes * and thus need to be detected and ignored by hand. That standard also * wants : rather than ; as separators but sequences containing : are currently * completely ignored by the parser. * * Subcommands 3 (CMY) and 4 (CMYK) are so insane there's no point in * supporting them. */ static int vc_t416_color(struct vc_data *vc, int i, void(*set_color)(struct vc_data *vc, const struct rgb *c)) { struct rgb c; i++; if (i > vc->vc_npar) return i; if (vc->vc_par[i] == 5 && i + 1 <= vc->vc_npar) { /* 256 colours */ i++; rgb_from_256(vc->vc_par[i], &c); } else if (vc->vc_par[i] == 2 && i + 3 <= vc->vc_npar) { /* 24 bit */ c.r = vc->vc_par[i + 1]; c.g = vc->vc_par[i + 2]; c.b = vc->vc_par[i + 3]; i += 3; } else return i; set_color(vc, &c); return i; } /* console_lock is held */ static void csi_m(struct vc_data *vc) { int i; for (i = 0; i <= vc->vc_npar; i++) switch (vc->vc_par[i]) { case 0: /* all attributes off */ default_attr(vc); break; case 1: vc->state.intensity = VCI_BOLD; break; case 2: vc->state.intensity = VCI_HALF_BRIGHT; break; case 3: vc->state.italic = true; break; case 21: /* * No console drivers support double underline, so * convert it to a single underline. */ case 4: vc->state.underline = true; break; case 5: vc->state.blink = true; break; case 7: vc->state.reverse = true; break; case 10: /* ANSI X3.64-1979 (SCO-ish?) * Select primary font, don't display control chars if * defined, don't set bit 8 on output. */ vc->vc_translate = set_translate(vc->state.Gx_charset[vc->state.charset], vc); vc->vc_disp_ctrl = 0; vc->vc_toggle_meta = 0; break; case 11: /* ANSI X3.64-1979 (SCO-ish?) * Select first alternate font, lets chars < 32 be * displayed as ROM chars. */ vc->vc_translate = set_translate(IBMPC_MAP, vc); vc->vc_disp_ctrl = 1; vc->vc_toggle_meta = 0; break; case 12: /* ANSI X3.64-1979 (SCO-ish?) * Select second alternate font, toggle high bit * before displaying as ROM char. */ vc->vc_translate = set_translate(IBMPC_MAP, vc); vc->vc_disp_ctrl = 1; vc->vc_toggle_meta = 1; break; case 22: vc->state.intensity = VCI_NORMAL; break; case 23: vc->state.italic = false; break; case 24: vc->state.underline = false; break; case 25: vc->state.blink = false; break; case 27: vc->state.reverse = false; break; case 38: i = vc_t416_color(vc, i, rgb_foreground); break; case 48: i = vc_t416_color(vc, i, rgb_background); break; case 39: vc->state.color = (vc->vc_def_color & 0x0f) | (vc->state.color & 0xf0); break; case 49: vc->state.color = (vc->vc_def_color & 0xf0) | (vc->state.color & 0x0f); break; default: if (vc->vc_par[i] >= 90 && vc->vc_par[i] <= 107) { if (vc->vc_par[i] < 100) vc->state.intensity = VCI_BOLD; vc->vc_par[i] -= 60; } if (vc->vc_par[i] >= 30 && vc->vc_par[i] <= 37) vc->state.color = color_table[vc->vc_par[i] - 30] | (vc->state.color & 0xf0); else if (vc->vc_par[i] >= 40 && vc->vc_par[i] <= 47) vc->state.color = (color_table[vc->vc_par[i] - 40] << 4) | (vc->state.color & 0x0f); break; } update_attr(vc); } static void respond_string(const char *p, size_t len, struct tty_port *port) { tty_insert_flip_string(port, p, len); tty_flip_buffer_push(port); } static void cursor_report(struct vc_data *vc, struct tty_struct *tty) { char buf[40]; int len; len = sprintf(buf, "\033[%d;%dR", vc->state.y + (vc->vc_decom ? vc->vc_top + 1 : 1), vc->state.x + 1); respond_string(buf, len, tty->port); } static inline void status_report(struct tty_struct *tty) { static const char teminal_ok[] = "\033[0n"; respond_string(teminal_ok, strlen(teminal_ok), tty->port); } static inline void respond_ID(struct tty_struct *tty) { /* terminal answer to an ESC-Z or csi0c query. */ static const char vt102_id[] = "\033[?6c"; respond_string(vt102_id, strlen(vt102_id), tty->port); } void mouse_report(struct tty_struct *tty, int butt, int mrx, int mry) { char buf[8]; int len; len = sprintf(buf, "\033[M%c%c%c", (char)(' ' + butt), (char)('!' + mrx), (char)('!' + mry)); respond_string(buf, len, tty->port); } /* invoked via ioctl(TIOCLINUX) and through set_selection_user */ int mouse_reporting(void) { return vc_cons[fg_console].d->vc_report_mouse; } /* console_lock is held */ static void set_mode(struct vc_data *vc, int on_off) { int i; for (i = 0; i <= vc->vc_npar; i++) if (vc->vc_priv == EPdec) { switch(vc->vc_par[i]) { /* DEC private modes set/reset */ case 1: /* Cursor keys send ^[Ox/^[[x */ if (on_off) set_kbd(vc, decckm); else clr_kbd(vc, decckm); break; case 3: /* 80/132 mode switch unimplemented */ #if 0 vc_resize(deccolm ? 132 : 80, vc->vc_rows); /* this alone does not suffice; some user mode utility has to change the hardware regs */ #endif break; case 5: /* Inverted screen on/off */ if (vc->vc_decscnm != on_off) { vc->vc_decscnm = on_off; invert_screen(vc, 0, vc->vc_screenbuf_size, false); update_attr(vc); } break; case 6: /* Origin relative/absolute */ vc->vc_decom = on_off; gotoxay(vc, 0, 0); break; case 7: /* Autowrap on/off */ vc->vc_decawm = on_off; break; case 8: /* Autorepeat on/off */ if (on_off) set_kbd(vc, decarm); else clr_kbd(vc, decarm); break; case 9: vc->vc_report_mouse = on_off ? 1 : 0; break; case 25: /* Cursor on/off */ vc->vc_deccm = on_off; break; case 1000: vc->vc_report_mouse = on_off ? 2 : 0; break; } } else { switch(vc->vc_par[i]) { /* ANSI modes set/reset */ case 3: /* Monitor (display ctrls) */ vc->vc_disp_ctrl = on_off; break; case 4: /* Insert Mode on/off */ vc->vc_decim = on_off; break; case 20: /* Lf, Enter == CrLf/Lf */ if (on_off) set_kbd(vc, lnm); else clr_kbd(vc, lnm); break; } } } /* console_lock is held */ static void setterm_command(struct vc_data *vc) { switch (vc->vc_par[0]) { case 1: /* set color for underline mode */ if (vc->vc_can_do_color && vc->vc_par[1] < 16) { vc->vc_ulcolor = color_table[vc->vc_par[1]]; if (vc->state.underline) update_attr(vc); } break; case 2: /* set color for half intensity mode */ if (vc->vc_can_do_color && vc->vc_par[1] < 16) { vc->vc_halfcolor = color_table[vc->vc_par[1]]; if (vc->state.intensity == VCI_HALF_BRIGHT) update_attr(vc); } break; case 8: /* store colors as defaults */ vc->vc_def_color = vc->vc_attr; if (vc->vc_hi_font_mask == 0x100) vc->vc_def_color >>= 1; default_attr(vc); update_attr(vc); break; case 9: /* set blanking interval */ blankinterval = min(vc->vc_par[1], 60U) * 60; poke_blanked_console(); break; case 10: /* set bell frequency in Hz */ if (vc->vc_npar >= 1) vc->vc_bell_pitch = vc->vc_par[1]; else vc->vc_bell_pitch = DEFAULT_BELL_PITCH; break; case 11: /* set bell duration in msec */ if (vc->vc_npar >= 1) vc->vc_bell_duration = (vc->vc_par[1] < 2000) ? msecs_to_jiffies(vc->vc_par[1]) : 0; else vc->vc_bell_duration = DEFAULT_BELL_DURATION; break; case 12: /* bring specified console to the front */ if (vc->vc_par[1] >= 1 && vc_cons_allocated(vc->vc_par[1] - 1)) set_console(vc->vc_par[1] - 1); break; case 13: /* unblank the screen */ poke_blanked_console(); break; case 14: /* set vesa powerdown interval */ vesa_off_interval = min(vc->vc_par[1], 60U) * 60 * HZ; break; case 15: /* activate the previous console */ set_console(last_console); break; case 16: /* set cursor blink duration in msec */ if (vc->vc_npar >= 1 && vc->vc_par[1] >= 50 && vc->vc_par[1] <= USHRT_MAX) vc->vc_cur_blink_ms = vc->vc_par[1]; else vc->vc_cur_blink_ms = DEFAULT_CURSOR_BLINK_MS; break; } } /* console_lock is held */ static void csi_at(struct vc_data *vc, unsigned int nr) { if (nr > vc->vc_cols - vc->state.x) nr = vc->vc_cols - vc->state.x; else if (!nr) nr = 1; insert_char(vc, nr); } /* console_lock is held */ static void csi_L(struct vc_data *vc, unsigned int nr) { if (nr > vc->vc_rows - vc->state.y) nr = vc->vc_rows - vc->state.y; else if (!nr) nr = 1; con_scroll(vc, vc->state.y, vc->vc_bottom, SM_DOWN, nr); vc->vc_need_wrap = 0; } /* console_lock is held */ static void csi_P(struct vc_data *vc, unsigned int nr) { if (nr > vc->vc_cols - vc->state.x) nr = vc->vc_cols - vc->state.x; else if (!nr) nr = 1; delete_char(vc, nr); } /* console_lock is held */ static void csi_M(struct vc_data *vc, unsigned int nr) { if (nr > vc->vc_rows - vc->state.y) nr = vc->vc_rows - vc->state.y; else if (!nr) nr=1; con_scroll(vc, vc->state.y, vc->vc_bottom, SM_UP, nr); vc->vc_need_wrap = 0; } /* console_lock is held (except via vc_init->reset_terminal */ static void save_cur(struct vc_data *vc) { memcpy(&vc->saved_state, &vc->state, sizeof(vc->state)); } /* console_lock is held */ static void restore_cur(struct vc_data *vc) { memcpy(&vc->state, &vc->saved_state, sizeof(vc->state)); gotoxy(vc, vc->state.x, vc->state.y); vc->vc_translate = set_translate(vc->state.Gx_charset[vc->state.charset], vc); update_attr(vc); vc->vc_need_wrap = 0; } enum { ESnormal, ESesc, ESsquare, ESgetpars, ESfunckey, EShash, ESsetG0, ESsetG1, ESpercent, EScsiignore, ESnonstd, ESpalette, ESosc, ESapc, ESpm, ESdcs }; /* console_lock is held (except via vc_init()) */ static void reset_terminal(struct vc_data *vc, int do_clear) { unsigned int i; vc->vc_top = 0; vc->vc_bottom = vc->vc_rows; vc->vc_state = ESnormal; vc->vc_priv = EPecma; vc->vc_translate = set_translate(LAT1_MAP, vc); vc->state.Gx_charset[0] = LAT1_MAP; vc->state.Gx_charset[1] = GRAF_MAP; vc->state.charset = 0; vc->vc_need_wrap = 0; vc->vc_report_mouse = 0; vc->vc_utf = default_utf8; vc->vc_utf_count = 0; vc->vc_disp_ctrl = 0; vc->vc_toggle_meta = 0; vc->vc_decscnm = 0; vc->vc_decom = 0; vc->vc_decawm = 1; vc->vc_deccm = global_cursor_default; vc->vc_decim = 0; vt_reset_keyboard(vc->vc_num); vc->vc_cursor_type = cur_default; vc->vc_complement_mask = vc->vc_s_complement_mask; default_attr(vc); update_attr(vc); bitmap_zero(vc->vc_tab_stop, VC_TABSTOPS_COUNT); for (i = 0; i < VC_TABSTOPS_COUNT; i += 8) set_bit(i, vc->vc_tab_stop); vc->vc_bell_pitch = DEFAULT_BELL_PITCH; vc->vc_bell_duration = DEFAULT_BELL_DURATION; vc->vc_cur_blink_ms = DEFAULT_CURSOR_BLINK_MS; gotoxy(vc, 0, 0); save_cur(vc); if (do_clear) csi_J(vc, 2); } static void vc_setGx(struct vc_data *vc, unsigned int which, int c) { unsigned char *charset = &vc->state.Gx_charset[which]; switch (c) { case '0': *charset = GRAF_MAP; break; case 'B': *charset = LAT1_MAP; break; case 'U': *charset = IBMPC_MAP; break; case 'K': *charset = USER_MAP; break; } if (vc->state.charset == which) vc->vc_translate = set_translate(*charset, vc); } /* is this state an ANSI control string? */ static bool ansi_control_string(unsigned int state) { if (state == ESosc || state == ESapc || state == ESpm || state == ESdcs) return true; return false; } /* console_lock is held */ static void do_con_trol(struct tty_struct *tty, struct vc_data *vc, int c) { /* * Control characters can be used in the _middle_ * of an escape sequence, aside from ANSI control strings. */ if (ansi_control_string(vc->vc_state) && c >= 8 && c <= 13) return; switch (c) { case 0: return; case 7: if (ansi_control_string(vc->vc_state)) vc->vc_state = ESnormal; else if (vc->vc_bell_duration) kd_mksound(vc->vc_bell_pitch, vc->vc_bell_duration); return; case 8: bs(vc); return; case 9: vc->vc_pos -= (vc->state.x << 1); vc->state.x = find_next_bit(vc->vc_tab_stop, min(vc->vc_cols - 1, VC_TABSTOPS_COUNT), vc->state.x + 1); if (vc->state.x >= VC_TABSTOPS_COUNT) vc->state.x = vc->vc_cols - 1; vc->vc_pos += (vc->state.x << 1); notify_write(vc, '\t'); return; case 10: case 11: case 12: lf(vc); if (!is_kbd(vc, lnm)) return; fallthrough; case 13: cr(vc); return; case 14: vc->state.charset = 1; vc->vc_translate = set_translate(vc->state.Gx_charset[1], vc); vc->vc_disp_ctrl = 1; return; case 15: vc->state.charset = 0; vc->vc_translate = set_translate(vc->state.Gx_charset[0], vc); vc->vc_disp_ctrl = 0; return; case 24: case 26: vc->vc_state = ESnormal; return; case 27: vc->vc_state = ESesc; return; case 127: del(vc); return; case 128+27: vc->vc_state = ESsquare; return; } switch(vc->vc_state) { case ESesc: vc->vc_state = ESnormal; switch (c) { case '[': vc->vc_state = ESsquare; return; case ']': vc->vc_state = ESnonstd; return; case '_': vc->vc_state = ESapc; return; case '^': vc->vc_state = ESpm; return; case '%': vc->vc_state = ESpercent; return; case 'E': cr(vc); lf(vc); return; case 'M': ri(vc); return; case 'D': lf(vc); return; case 'H': if (vc->state.x < VC_TABSTOPS_COUNT) set_bit(vc->state.x, vc->vc_tab_stop); return; case 'P': vc->vc_state = ESdcs; return; case 'Z': respond_ID(tty); return; case '7': save_cur(vc); return; case '8': restore_cur(vc); return; case '(': vc->vc_state = ESsetG0; return; case ')': vc->vc_state = ESsetG1; return; case '#': vc->vc_state = EShash; return; case 'c': reset_terminal(vc, 1); return; case '>': /* Numeric keypad */ clr_kbd(vc, kbdapplic); return; case '=': /* Appl. keypad */ set_kbd(vc, kbdapplic); return; } return; case ESnonstd: if (c=='P') { /* palette escape sequence */ for (vc->vc_npar = 0; vc->vc_npar < NPAR; vc->vc_npar++) vc->vc_par[vc->vc_npar] = 0; vc->vc_npar = 0; vc->vc_state = ESpalette; return; } else if (c=='R') { /* reset palette */ reset_palette(vc); vc->vc_state = ESnormal; } else if (c>='0' && c<='9') vc->vc_state = ESosc; else vc->vc_state = ESnormal; return; case ESpalette: if (isxdigit(c)) { vc->vc_par[vc->vc_npar++] = hex_to_bin(c); if (vc->vc_npar == 7) { int i = vc->vc_par[0] * 3, j = 1; vc->vc_palette[i] = 16 * vc->vc_par[j++]; vc->vc_palette[i++] += vc->vc_par[j++]; vc->vc_palette[i] = 16 * vc->vc_par[j++]; vc->vc_palette[i++] += vc->vc_par[j++]; vc->vc_palette[i] = 16 * vc->vc_par[j++]; vc->vc_palette[i] += vc->vc_par[j]; set_palette(vc); vc->vc_state = ESnormal; } } else vc->vc_state = ESnormal; return; case ESsquare: for (vc->vc_npar = 0; vc->vc_npar < NPAR; vc->vc_npar++) vc->vc_par[vc->vc_npar] = 0; vc->vc_npar = 0; vc->vc_state = ESgetpars; if (c == '[') { /* Function key */ vc->vc_state=ESfunckey; return; } switch (c) { case '?': vc->vc_priv = EPdec; return; case '>': vc->vc_priv = EPgt; return; case '=': vc->vc_priv = EPeq; return; case '<': vc->vc_priv = EPlt; return; } vc->vc_priv = EPecma; fallthrough; case ESgetpars: if (c == ';' && vc->vc_npar < NPAR - 1) { vc->vc_npar++; return; } else if (c>='0' && c<='9') { vc->vc_par[vc->vc_npar] *= 10; vc->vc_par[vc->vc_npar] += c - '0'; return; } if (c >= 0x20 && c <= 0x3f) { /* 0x2x, 0x3a and 0x3c - 0x3f */ vc->vc_state = EScsiignore; return; } vc->vc_state = ESnormal; switch(c) { case 'h': if (vc->vc_priv <= EPdec) set_mode(vc, 1); return; case 'l': if (vc->vc_priv <= EPdec) set_mode(vc, 0); return; case 'c': if (vc->vc_priv == EPdec) { if (vc->vc_par[0]) vc->vc_cursor_type = CUR_MAKE(vc->vc_par[0], vc->vc_par[1], vc->vc_par[2]); else vc->vc_cursor_type = cur_default; return; } break; case 'm': if (vc->vc_priv == EPdec) { clear_selection(); if (vc->vc_par[0]) vc->vc_complement_mask = vc->vc_par[0] << 8 | vc->vc_par[1]; else vc->vc_complement_mask = vc->vc_s_complement_mask; return; } break; case 'n': if (vc->vc_priv == EPecma) { if (vc->vc_par[0] == 5) status_report(tty); else if (vc->vc_par[0] == 6) cursor_report(vc, tty); } return; } if (vc->vc_priv != EPecma) { vc->vc_priv = EPecma; return; } switch(c) { case 'G': case '`': if (vc->vc_par[0]) vc->vc_par[0]--; gotoxy(vc, vc->vc_par[0], vc->state.y); return; case 'A': if (!vc->vc_par[0]) vc->vc_par[0]++; gotoxy(vc, vc->state.x, vc->state.y - vc->vc_par[0]); return; case 'B': case 'e': if (!vc->vc_par[0]) vc->vc_par[0]++; gotoxy(vc, vc->state.x, vc->state.y + vc->vc_par[0]); return; case 'C': case 'a': if (!vc->vc_par[0]) vc->vc_par[0]++; gotoxy(vc, vc->state.x + vc->vc_par[0], vc->state.y); return; case 'D': if (!vc->vc_par[0]) vc->vc_par[0]++; gotoxy(vc, vc->state.x - vc->vc_par[0], vc->state.y); return; case 'E': if (!vc->vc_par[0]) vc->vc_par[0]++; gotoxy(vc, 0, vc->state.y + vc->vc_par[0]); return; case 'F': if (!vc->vc_par[0]) vc->vc_par[0]++; gotoxy(vc, 0, vc->state.y - vc->vc_par[0]); return; case 'd': if (vc->vc_par[0]) vc->vc_par[0]--; gotoxay(vc, vc->state.x ,vc->vc_par[0]); return; case 'H': case 'f': if (vc->vc_par[0]) vc->vc_par[0]--; if (vc->vc_par[1]) vc->vc_par[1]--; gotoxay(vc, vc->vc_par[1], vc->vc_par[0]); return; case 'J': csi_J(vc, vc->vc_par[0]); return; case 'K': csi_K(vc, vc->vc_par[0]); return; case 'L': csi_L(vc, vc->vc_par[0]); return; case 'M': csi_M(vc, vc->vc_par[0]); return; case 'P': csi_P(vc, vc->vc_par[0]); return; case 'c': if (!vc->vc_par[0]) respond_ID(tty); return; case 'g': if (!vc->vc_par[0] && vc->state.x < VC_TABSTOPS_COUNT) set_bit(vc->state.x, vc->vc_tab_stop); else if (vc->vc_par[0] == 3) bitmap_zero(vc->vc_tab_stop, VC_TABSTOPS_COUNT); return; case 'm': csi_m(vc); return; case 'q': /* DECLL - but only 3 leds */ /* map 0,1,2,3 to 0,1,2,4 */ if (vc->vc_par[0] < 4) vt_set_led_state(vc->vc_num, (vc->vc_par[0] < 3) ? vc->vc_par[0] : 4); return; case 'r': if (!vc->vc_par[0]) vc->vc_par[0]++; if (!vc->vc_par[1]) vc->vc_par[1] = vc->vc_rows; /* Minimum allowed region is 2 lines */ if (vc->vc_par[0] < vc->vc_par[1] && vc->vc_par[1] <= vc->vc_rows) { vc->vc_top = vc->vc_par[0] - 1; vc->vc_bottom = vc->vc_par[1]; gotoxay(vc, 0, 0); } return; case 's': save_cur(vc); return; case 'u': restore_cur(vc); return; case 'X': csi_X(vc, vc->vc_par[0]); return; case '@': csi_at(vc, vc->vc_par[0]); return; case ']': /* setterm functions */ setterm_command(vc); return; } return; case EScsiignore: if (c >= 0x20 && c <= 0x3f) return; vc->vc_state = ESnormal; return; case ESpercent: vc->vc_state = ESnormal; switch (c) { case '@': /* defined in ISO 2022 */ vc->vc_utf = 0; return; case 'G': /* prelim official escape code */ case '8': /* retained for compatibility */ vc->vc_utf = 1; return; } return; case ESfunckey: vc->vc_state = ESnormal; return; case EShash: vc->vc_state = ESnormal; if (c == '8') { /* DEC screen alignment test. kludge :-) */ vc->vc_video_erase_char = (vc->vc_video_erase_char & 0xff00) | 'E'; csi_J(vc, 2); vc->vc_video_erase_char = (vc->vc_video_erase_char & 0xff00) | ' '; do_update_region(vc, vc->vc_origin, vc->vc_screenbuf_size / 2); } return; case ESsetG0: vc_setGx(vc, 0, c); vc->vc_state = ESnormal; return; case ESsetG1: vc_setGx(vc, 1, c); vc->vc_state = ESnormal; return; case ESapc: return; case ESosc: return; case ESpm: return; case ESdcs: return; default: vc->vc_state = ESnormal; } } /* is_double_width() is based on the wcwidth() implementation by * Markus Kuhn -- 2007-05-26 (Unicode 5.0) * Latest version: https://www.cl.cam.ac.uk/~mgk25/ucs/wcwidth.c */ struct interval { uint32_t first; uint32_t last; }; static int ucs_cmp(const void *key, const void *elt) { uint32_t ucs = *(uint32_t *)key; struct interval e = *(struct interval *) elt; if (ucs > e.last) return 1; else if (ucs < e.first) return -1; return 0; } static int is_double_width(uint32_t ucs) { static const struct interval double_width[] = { { 0x1100, 0x115F }, { 0x2329, 0x232A }, { 0x2E80, 0x303E }, { 0x3040, 0xA4CF }, { 0xAC00, 0xD7A3 }, { 0xF900, 0xFAFF }, { 0xFE10, 0xFE19 }, { 0xFE30, 0xFE6F }, { 0xFF00, 0xFF60 }, { 0xFFE0, 0xFFE6 }, { 0x20000, 0x2FFFD }, { 0x30000, 0x3FFFD } }; if (ucs < double_width[0].first || ucs > double_width[ARRAY_SIZE(double_width) - 1].last) return 0; return bsearch(&ucs, double_width, ARRAY_SIZE(double_width), sizeof(struct interval), ucs_cmp) != NULL; } struct vc_draw_region { unsigned long from, to; int x; }; static void con_flush(struct vc_data *vc, struct vc_draw_region *draw) { if (draw->x < 0) return; vc->vc_sw->con_putcs(vc, (u16 *)draw->from, (u16 *)draw->to - (u16 *)draw->from, vc->state.y, draw->x); draw->x = -1; } static inline int vc_translate_ascii(const struct vc_data *vc, int c) { if (IS_ENABLED(CONFIG_CONSOLE_TRANSLATIONS)) { if (vc->vc_toggle_meta) c |= 0x80; return vc->vc_translate[c]; } return c; } /** * vc_sanitize_unicode -- Replace invalid Unicode code points with U+FFFD * @c: the received character, or U+FFFD for invalid sequences. */ static inline int vc_sanitize_unicode(const int c) { if ((c >= 0xd800 && c <= 0xdfff) || c == 0xfffe || c == 0xffff) return 0xfffd; return c; } /** * vc_translate_unicode -- Combine UTF-8 into Unicode in @vc_utf_char * @vc: virtual console * @c: character to translate * @rescan: we return true if we need more (continuation) data * * @vc_utf_char is the being-constructed unicode character. * @vc_utf_count is the number of continuation bytes still expected to arrive. * @vc_npar is the number of continuation bytes arrived so far. */ static int vc_translate_unicode(struct vc_data *vc, int c, bool *rescan) { static const u32 utf8_length_changes[] = { 0x0000007f, 0x000007ff, 0x0000ffff, 0x001fffff, 0x03ffffff, 0x7fffffff }; /* Continuation byte received */ if ((c & 0xc0) == 0x80) { /* Unexpected continuation byte? */ if (!vc->vc_utf_count) return 0xfffd; vc->vc_utf_char = (vc->vc_utf_char << 6) | (c & 0x3f); vc->vc_npar++; if (--vc->vc_utf_count) goto need_more_bytes; /* Got a whole character */ c = vc->vc_utf_char; /* Reject overlong sequences */ if (c <= utf8_length_changes[vc->vc_npar - 1] || c > utf8_length_changes[vc->vc_npar]) return 0xfffd; return vc_sanitize_unicode(c); } /* Single ASCII byte or first byte of a sequence received */ if (vc->vc_utf_count) { /* Continuation byte expected */ *rescan = true; vc->vc_utf_count = 0; return 0xfffd; } /* Nothing to do if an ASCII byte was received */ if (c <= 0x7f) return c; /* First byte of a multibyte sequence received */ vc->vc_npar = 0; if ((c & 0xe0) == 0xc0) { vc->vc_utf_count = 1; vc->vc_utf_char = (c & 0x1f); } else if ((c & 0xf0) == 0xe0) { vc->vc_utf_count = 2; vc->vc_utf_char = (c & 0x0f); } else if ((c & 0xf8) == 0xf0) { vc->vc_utf_count = 3; vc->vc_utf_char = (c & 0x07); } else if ((c & 0xfc) == 0xf8) { vc->vc_utf_count = 4; vc->vc_utf_char = (c & 0x03); } else if ((c & 0xfe) == 0xfc) { vc->vc_utf_count = 5; vc->vc_utf_char = (c & 0x01); } else { /* 254 and 255 are invalid */ return 0xfffd; } need_more_bytes: return -1; } static int vc_translate(struct vc_data *vc, int *c, bool *rescan) { /* Do no translation at all in control states */ if (vc->vc_state != ESnormal) return *c; if (vc->vc_utf && !vc->vc_disp_ctrl) return *c = vc_translate_unicode(vc, *c, rescan); /* no utf or alternate charset mode */ return vc_translate_ascii(vc, *c); } static inline unsigned char vc_invert_attr(const struct vc_data *vc) { if (!vc->vc_can_do_color) return vc->vc_attr ^ 0x08; if (vc->vc_hi_font_mask == 0x100) return (vc->vc_attr & 0x11) | ((vc->vc_attr & 0xe0) >> 4) | ((vc->vc_attr & 0x0e) << 4); return (vc->vc_attr & 0x88) | ((vc->vc_attr & 0x70) >> 4) | ((vc->vc_attr & 0x07) << 4); } static bool vc_is_control(struct vc_data *vc, int tc, int c) { /* * A bitmap for codes <32. A bit of 1 indicates that the code * corresponding to that bit number invokes some special action (such * as cursor movement) and should not be displayed as a glyph unless * the disp_ctrl mode is explicitly enabled. */ static const u32 CTRL_ACTION = 0x0d00ff81; /* Cannot be overridden by disp_ctrl */ static const u32 CTRL_ALWAYS = 0x0800f501; if (vc->vc_state != ESnormal) return true; if (!tc) return true; /* * If the original code was a control character we only allow a glyph * to be displayed if the code is not normally used (such as for cursor * movement) or if the disp_ctrl mode has been explicitly enabled. * Certain characters (as given by the CTRL_ALWAYS bitmap) are always * displayed as control characters, as the console would be pretty * useless without them; to display an arbitrary font position use the * direct-to-font zone in UTF-8 mode. */ if (c < 32) { if (vc->vc_disp_ctrl) return CTRL_ALWAYS & BIT(c); else return vc->vc_utf || (CTRL_ACTION & BIT(c)); } if (c == 127 && !vc->vc_disp_ctrl) return true; if (c == 128 + 27) return true; return false; } static int vc_con_write_normal(struct vc_data *vc, int tc, int c, struct vc_draw_region *draw) { int next_c; unsigned char vc_attr = vc->vc_attr; u16 himask = vc->vc_hi_font_mask, charmask = himask ? 0x1ff : 0xff; u8 width = 1; bool inverse = false; if (vc->vc_utf && !vc->vc_disp_ctrl) { if (is_double_width(c)) width = 2; } /* Now try to find out how to display it */ tc = conv_uni_to_pc(vc, tc); if (tc & ~charmask) { if (tc == -1 || tc == -2) return -1; /* nothing to display */ /* Glyph not found */ if ((!vc->vc_utf || vc->vc_disp_ctrl || c < 128) && !(c & ~charmask)) { /* * In legacy mode use the glyph we get by a 1:1 * mapping. * This would make absolutely no sense with Unicode in * mind, but do this for ASCII characters since a font * may lack Unicode mapping info and we don't want to * end up with having question marks only. */ tc = c; } else { /* * Display U+FFFD. If it's not found, display an inverse * question mark. */ tc = conv_uni_to_pc(vc, 0xfffd); if (tc < 0) { inverse = true; tc = conv_uni_to_pc(vc, '?'); if (tc < 0) tc = '?'; vc_attr = vc_invert_attr(vc); con_flush(vc, draw); } } } next_c = c; while (1) { if (vc->vc_need_wrap || vc->vc_decim) con_flush(vc, draw); if (vc->vc_need_wrap) { cr(vc); lf(vc); } if (vc->vc_decim) insert_char(vc, 1); vc_uniscr_putc(vc, next_c); if (himask) tc = ((tc & 0x100) ? himask : 0) | (tc & 0xff); tc |= (vc_attr << 8) & ~himask; scr_writew(tc, (u16 *)vc->vc_pos); if (con_should_update(vc) && draw->x < 0) { draw->x = vc->state.x; draw->from = vc->vc_pos; } if (vc->state.x == vc->vc_cols - 1) { vc->vc_need_wrap = vc->vc_decawm; draw->to = vc->vc_pos + 2; } else { vc->state.x++; draw->to = (vc->vc_pos += 2); } if (!--width) break; /* A space is printed in the second column */ tc = conv_uni_to_pc(vc, ' '); if (tc < 0) tc = ' '; next_c = ' '; } notify_write(vc, c); if (inverse) con_flush(vc, draw); return 0; } /* acquires console_lock */ static int do_con_write(struct tty_struct *tty, const u8 *buf, int count) { struct vc_draw_region draw = { .x = -1, }; int c, tc, n = 0; unsigned int currcons; struct vc_data *vc; struct vt_notifier_param param; bool rescan; if (in_interrupt()) return count; console_lock(); vc = tty->driver_data; if (vc == NULL) { pr_err("vt: argh, driver_data is NULL !\n"); console_unlock(); return 0; } currcons = vc->vc_num; if (!vc_cons_allocated(currcons)) { /* could this happen? */ pr_warn_once("con_write: tty %d not allocated\n", currcons+1); console_unlock(); return 0; } /* undraw cursor first */ if (con_is_fg(vc)) hide_cursor(vc); param.vc = vc; while (!tty->flow.stopped && count) { int orig = *buf; buf++; n++; count--; rescan_last_byte: c = orig; rescan = false; tc = vc_translate(vc, &c, &rescan); if (tc == -1) continue; param.c = tc; if (atomic_notifier_call_chain(&vt_notifier_list, VT_PREWRITE, ¶m) == NOTIFY_STOP) continue; if (vc_is_control(vc, tc, c)) { con_flush(vc, &draw); do_con_trol(tty, vc, orig); continue; } if (vc_con_write_normal(vc, tc, c, &draw) < 0) continue; if (rescan) goto rescan_last_byte; } con_flush(vc, &draw); console_conditional_schedule(); notify_update(vc); console_unlock(); return n; } /* * This is the console switching callback. * * Doing console switching in a process context allows * us to do the switches asynchronously (needed when we want * to switch due to a keyboard interrupt). Synchronization * with other console code and prevention of re-entrancy is * ensured with console_lock. */ static void console_callback(struct work_struct *ignored) { console_lock(); if (want_console >= 0) { if (want_console != fg_console && vc_cons_allocated(want_console)) { hide_cursor(vc_cons[fg_console].d); change_console(vc_cons[want_console].d); /* we only changed when the console had already been allocated - a new console is not created in an interrupt routine */ } want_console = -1; } if (do_poke_blanked_console) { /* do not unblank for a LED change */ do_poke_blanked_console = 0; poke_blanked_console(); } if (scrollback_delta) { struct vc_data *vc = vc_cons[fg_console].d; clear_selection(); if (vc->vc_mode == KD_TEXT && vc->vc_sw->con_scrolldelta) vc->vc_sw->con_scrolldelta(vc, scrollback_delta); scrollback_delta = 0; } if (blank_timer_expired) { do_blank_screen(0); blank_timer_expired = 0; } notify_update(vc_cons[fg_console].d); console_unlock(); } int set_console(int nr) { struct vc_data *vc = vc_cons[fg_console].d; if (!vc_cons_allocated(nr) || vt_dont_switch || (vc->vt_mode.mode == VT_AUTO && vc->vc_mode == KD_GRAPHICS)) { /* * Console switch will fail in console_callback() or * change_console() so there is no point scheduling * the callback * * Existing set_console() users don't check the return * value so this shouldn't break anything */ return -EINVAL; } want_console = nr; schedule_console_callback(); return 0; } struct tty_driver *console_driver; #ifdef CONFIG_VT_CONSOLE /** * vt_kmsg_redirect() - Sets/gets the kernel message console * @new: The new virtual terminal number or -1 if the console should stay * unchanged * * By default, the kernel messages are always printed on the current virtual * console. However, the user may modify that default with the * TIOCL_SETKMSGREDIRECT ioctl call. * * This function sets the kernel message console to be @new. It returns the old * virtual console number. The virtual terminal number 0 (both as parameter and * return value) means no redirection (i.e. always printed on the currently * active console). * * The parameter -1 means that only the current console is returned, but the * value is not modified. You may use the macro vt_get_kmsg_redirect() in that * case to make the code more understandable. * * When the kernel is compiled without CONFIG_VT_CONSOLE, this function ignores * the parameter and always returns 0. */ int vt_kmsg_redirect(int new) { static int kmsg_con; if (new != -1) return xchg(&kmsg_con, new); else return kmsg_con; } /* * Console on virtual terminal * * The console must be locked when we get here. */ static void vt_console_print(struct console *co, const char *b, unsigned count) { struct vc_data *vc = vc_cons[fg_console].d; unsigned char c; static DEFINE_SPINLOCK(printing_lock); const ushort *start; ushort start_x, cnt; int kmsg_console; WARN_CONSOLE_UNLOCKED(); /* this protects against concurrent oops only */ if (!spin_trylock(&printing_lock)) return; kmsg_console = vt_get_kmsg_redirect(); if (kmsg_console && vc_cons_allocated(kmsg_console - 1)) vc = vc_cons[kmsg_console - 1].d; if (!vc_cons_allocated(fg_console)) { /* impossible */ /* printk("vt_console_print: tty %d not allocated ??\n", currcons+1); */ goto quit; } if (vc->vc_mode != KD_TEXT) goto quit; /* undraw cursor first */ if (con_is_fg(vc)) hide_cursor(vc); start = (ushort *)vc->vc_pos; start_x = vc->state.x; cnt = 0; while (count--) { c = *b++; if (c == 10 || c == 13 || c == 8 || vc->vc_need_wrap) { if (cnt && con_is_visible(vc)) vc->vc_sw->con_putcs(vc, start, cnt, vc->state.y, start_x); cnt = 0; if (c == 8) { /* backspace */ bs(vc); start = (ushort *)vc->vc_pos; start_x = vc->state.x; continue; } if (c != 13) lf(vc); cr(vc); start = (ushort *)vc->vc_pos; start_x = vc->state.x; if (c == 10 || c == 13) continue; } vc_uniscr_putc(vc, c); scr_writew((vc->vc_attr << 8) + c, (unsigned short *)vc->vc_pos); notify_write(vc, c); cnt++; if (vc->state.x == vc->vc_cols - 1) { vc->vc_need_wrap = 1; } else { vc->vc_pos += 2; vc->state.x++; } } if (cnt && con_is_visible(vc)) vc->vc_sw->con_putcs(vc, start, cnt, vc->state.y, start_x); set_cursor(vc); notify_update(vc); quit: spin_unlock(&printing_lock); } static struct tty_driver *vt_console_device(struct console *c, int *index) { *index = c->index ? c->index-1 : fg_console; return console_driver; } static int vt_console_setup(struct console *co, char *options) { return co->index >= MAX_NR_CONSOLES ? -EINVAL : 0; } static struct console vt_console_driver = { .name = "tty", .setup = vt_console_setup, .write = vt_console_print, .device = vt_console_device, .unblank = unblank_screen, .flags = CON_PRINTBUFFER, .index = -1, }; #endif /* * Handling of Linux-specific VC ioctls */ /* * Generally a bit racy with respect to console_lock();. * * There are some functions which don't need it. * * There are some functions which can sleep for arbitrary periods * (paste_selection) but we don't need the lock there anyway. * * set_selection_user has locking, and definitely needs it */ int tioclinux(struct tty_struct *tty, unsigned long arg) { char type, data; char __user *p = (char __user *)arg; int lines; int ret; if (current->signal->tty != tty && !capable(CAP_SYS_ADMIN)) return -EPERM; if (get_user(type, p)) return -EFAULT; ret = 0; switch (type) { case TIOCL_SETSEL: return set_selection_user((struct tiocl_selection __user *)(p+1), tty); case TIOCL_PASTESEL: return paste_selection(tty); case TIOCL_UNBLANKSCREEN: console_lock(); unblank_screen(); console_unlock(); break; case TIOCL_SELLOADLUT: console_lock(); ret = sel_loadlut(p); console_unlock(); break; case TIOCL_GETSHIFTSTATE: /* * Make it possible to react to Shift+Mousebutton. Note that * 'shift_state' is an undocumented kernel-internal variable; * programs not closely related to the kernel should not use * this. */ data = vt_get_shift_state(); return put_user(data, p); case TIOCL_GETMOUSEREPORTING: console_lock(); /* May be overkill */ data = mouse_reporting(); console_unlock(); return put_user(data, p); case TIOCL_SETVESABLANK: console_lock(); ret = set_vesa_blanking(p); console_unlock(); break; case TIOCL_GETKMSGREDIRECT: data = vt_get_kmsg_redirect(); return put_user(data, p); case TIOCL_SETKMSGREDIRECT: if (!capable(CAP_SYS_ADMIN)) return -EPERM; if (get_user(data, p+1)) return -EFAULT; vt_kmsg_redirect(data); break; case TIOCL_GETFGCONSOLE: /* * No locking needed as this is a transiently correct return * anyway if the caller hasn't disabled switching. */ return fg_console; case TIOCL_SCROLLCONSOLE: if (get_user(lines, (s32 __user *)(p+4))) return -EFAULT; /* * Needs the console lock here. Note that lots of other calls * need fixing before the lock is actually useful! */ console_lock(); scrollfront(vc_cons[fg_console].d, lines); console_unlock(); break; case TIOCL_BLANKSCREEN: /* until explicitly unblanked, not only poked */ console_lock(); ignore_poke = 1; do_blank_screen(0); console_unlock(); break; case TIOCL_BLANKEDSCREEN: return console_blanked; default: return -EINVAL; } return ret; } /* * /dev/ttyN handling */ static ssize_t con_write(struct tty_struct *tty, const u8 *buf, size_t count) { int retval; retval = do_con_write(tty, buf, count); con_flush_chars(tty); return retval; } static int con_put_char(struct tty_struct *tty, u8 ch) { return do_con_write(tty, &ch, 1); } static unsigned int con_write_room(struct tty_struct *tty) { if (tty->flow.stopped) return 0; return 32768; /* No limit, really; we're not buffering */ } /* * con_throttle and con_unthrottle are only used for * paste_selection(), which has to stuff in a large number of * characters... */ static void con_throttle(struct tty_struct *tty) { } static void con_unthrottle(struct tty_struct *tty) { struct vc_data *vc = tty->driver_data; wake_up_interruptible(&vc->paste_wait); } /* * Turn the Scroll-Lock LED on when the tty is stopped */ static void con_stop(struct tty_struct *tty) { int console_num; if (!tty) return; console_num = tty->index; if (!vc_cons_allocated(console_num)) return; vt_kbd_con_stop(console_num); } /* * Turn the Scroll-Lock LED off when the console is started */ static void con_start(struct tty_struct *tty) { int console_num; if (!tty) return; console_num = tty->index; if (!vc_cons_allocated(console_num)) return; vt_kbd_con_start(console_num); } static void con_flush_chars(struct tty_struct *tty) { struct vc_data *vc; if (in_interrupt()) /* from flush_to_ldisc */ return; /* if we race with con_close(), vt may be null */ console_lock(); vc = tty->driver_data; if (vc) set_cursor(vc); console_unlock(); } /* * Allocate the console screen memory. */ static int con_install(struct tty_driver *driver, struct tty_struct *tty) { unsigned int currcons = tty->index; struct vc_data *vc; int ret; console_lock(); ret = vc_allocate(currcons); if (ret) goto unlock; vc = vc_cons[currcons].d; /* Still being freed */ if (vc->port.tty) { ret = -ERESTARTSYS; goto unlock; } ret = tty_port_install(&vc->port, driver, tty); if (ret) goto unlock; tty->driver_data = vc; vc->port.tty = tty; tty_port_get(&vc->port); if (!tty->winsize.ws_row && !tty->winsize.ws_col) { tty->winsize.ws_row = vc_cons[currcons].d->vc_rows; tty->winsize.ws_col = vc_cons[currcons].d->vc_cols; } if (vc->vc_utf) tty->termios.c_iflag |= IUTF8; else tty->termios.c_iflag &= ~IUTF8; unlock: console_unlock(); return ret; } static int con_open(struct tty_struct *tty, struct file *filp) { /* everything done in install */ return 0; } static void con_close(struct tty_struct *tty, struct file *filp) { /* Nothing to do - we defer to shutdown */ } static void con_shutdown(struct tty_struct *tty) { struct vc_data *vc = tty->driver_data; BUG_ON(vc == NULL); console_lock(); vc->port.tty = NULL; console_unlock(); } static void con_cleanup(struct tty_struct *tty) { struct vc_data *vc = tty->driver_data; tty_port_put(&vc->port); } /* * We can't deal with anything but the N_TTY ldisc, * because we can sleep in our write() routine. */ static int con_ldisc_ok(struct tty_struct *tty, int ldisc) { return ldisc == N_TTY ? 0 : -EINVAL; } static int default_color = 7; /* white */ static int default_italic_color = 2; // green (ASCII) static int default_underline_color = 3; // cyan (ASCII) module_param_named(color, default_color, int, S_IRUGO | S_IWUSR); module_param_named(italic, default_italic_color, int, S_IRUGO | S_IWUSR); module_param_named(underline, default_underline_color, int, S_IRUGO | S_IWUSR); static void vc_init(struct vc_data *vc, int do_clear) { int j, k ; set_origin(vc); vc->vc_pos = vc->vc_origin; reset_vc(vc); for (j=k=0; j<16; j++) { vc->vc_palette[k++] = default_red[j] ; vc->vc_palette[k++] = default_grn[j] ; vc->vc_palette[k++] = default_blu[j] ; } vc->vc_def_color = default_color; vc->vc_ulcolor = default_underline_color; vc->vc_itcolor = default_italic_color; vc->vc_halfcolor = 0x08; /* grey */ init_waitqueue_head(&vc->paste_wait); reset_terminal(vc, do_clear); } /* * This routine initializes console interrupts, and does nothing * else. If you want the screen to clear, call tty_write with * the appropriate escape-sequence. */ static int __init con_init(void) { const char *display_desc = NULL; struct vc_data *vc; unsigned int currcons = 0, i; console_lock(); if (!conswitchp) conswitchp = &dummy_con; display_desc = conswitchp->con_startup(); if (!display_desc) { fg_console = 0; console_unlock(); return 0; } for (i = 0; i < MAX_NR_CON_DRIVER; i++) { struct con_driver *con_driver = ®istered_con_driver[i]; if (con_driver->con == NULL) { con_driver->con = conswitchp; con_driver->desc = display_desc; con_driver->flag = CON_DRIVER_FLAG_INIT; con_driver->first = 0; con_driver->last = MAX_NR_CONSOLES - 1; break; } } for (i = 0; i < MAX_NR_CONSOLES; i++) con_driver_map[i] = conswitchp; if (blankinterval) { blank_state = blank_normal_wait; mod_timer(&console_timer, jiffies + (blankinterval * HZ)); } for (currcons = 0; currcons < MIN_NR_CONSOLES; currcons++) { vc_cons[currcons].d = vc = kzalloc(sizeof(struct vc_data), GFP_NOWAIT); INIT_WORK(&vc_cons[currcons].SAK_work, vc_SAK); tty_port_init(&vc->port); visual_init(vc, currcons, 1); /* Assuming vc->vc_{cols,rows,screenbuf_size} are sane here. */ vc->vc_screenbuf = kzalloc(vc->vc_screenbuf_size, GFP_NOWAIT); vc_init(vc, currcons || !vc->vc_sw->con_save_screen); } currcons = fg_console = 0; master_display_fg = vc = vc_cons[currcons].d; set_origin(vc); save_screen(vc); gotoxy(vc, vc->state.x, vc->state.y); csi_J(vc, 0); update_screen(vc); pr_info("Console: %s %s %dx%d\n", vc->vc_can_do_color ? "colour" : "mono", display_desc, vc->vc_cols, vc->vc_rows); console_unlock(); #ifdef CONFIG_VT_CONSOLE register_console(&vt_console_driver); #endif return 0; } console_initcall(con_init); static const struct tty_operations con_ops = { .install = con_install, .open = con_open, .close = con_close, .write = con_write, .write_room = con_write_room, .put_char = con_put_char, .flush_chars = con_flush_chars, .ioctl = vt_ioctl, #ifdef CONFIG_COMPAT .compat_ioctl = vt_compat_ioctl, #endif .stop = con_stop, .start = con_start, .throttle = con_throttle, .unthrottle = con_unthrottle, .resize = vt_resize, .shutdown = con_shutdown, .cleanup = con_cleanup, .ldisc_ok = con_ldisc_ok, }; static struct cdev vc0_cdev; static ssize_t show_tty_active(struct device *dev, struct device_attribute *attr, char *buf) { return sprintf(buf, "tty%d\n", fg_console + 1); } static DEVICE_ATTR(active, S_IRUGO, show_tty_active, NULL); static struct attribute *vt_dev_attrs[] = { &dev_attr_active.attr, NULL }; ATTRIBUTE_GROUPS(vt_dev); int __init vty_init(const struct file_operations *console_fops) { cdev_init(&vc0_cdev, console_fops); if (cdev_add(&vc0_cdev, MKDEV(TTY_MAJOR, 0), 1) || register_chrdev_region(MKDEV(TTY_MAJOR, 0), 1, "/dev/vc/0") < 0) panic("Couldn't register /dev/tty0 driver\n"); tty0dev = device_create_with_groups(&tty_class, NULL, MKDEV(TTY_MAJOR, 0), NULL, vt_dev_groups, "tty0"); if (IS_ERR(tty0dev)) tty0dev = NULL; vcs_init(); console_driver = tty_alloc_driver(MAX_NR_CONSOLES, TTY_DRIVER_REAL_RAW | TTY_DRIVER_RESET_TERMIOS); if (IS_ERR(console_driver)) panic("Couldn't allocate console driver\n"); console_driver->name = "tty"; console_driver->name_base = 1; console_driver->major = TTY_MAJOR; console_driver->minor_start = 1; console_driver->type = TTY_DRIVER_TYPE_CONSOLE; console_driver->init_termios = tty_std_termios; if (default_utf8) console_driver->init_termios.c_iflag |= IUTF8; tty_set_operations(console_driver, &con_ops); if (tty_register_driver(console_driver)) panic("Couldn't register console driver\n"); kbd_init(); console_map_init(); #ifdef CONFIG_MDA_CONSOLE mda_console_init(); #endif return 0; } static struct class *vtconsole_class; static int do_bind_con_driver(const struct consw *csw, int first, int last, int deflt) { struct module *owner = csw->owner; const char *desc = NULL; struct con_driver *con_driver; int i, j = -1, k = -1, retval = -ENODEV; if (!try_module_get(owner)) return -ENODEV; WARN_CONSOLE_UNLOCKED(); /* check if driver is registered */ for (i = 0; i < MAX_NR_CON_DRIVER; i++) { con_driver = ®istered_con_driver[i]; if (con_driver->con == csw) { desc = con_driver->desc; retval = 0; break; } } if (retval) goto err; if (!(con_driver->flag & CON_DRIVER_FLAG_INIT)) { csw->con_startup(); con_driver->flag |= CON_DRIVER_FLAG_INIT; } if (deflt) { if (conswitchp) module_put(conswitchp->owner); __module_get(owner); conswitchp = csw; } first = max(first, con_driver->first); last = min(last, con_driver->last); for (i = first; i <= last; i++) { int old_was_color; struct vc_data *vc = vc_cons[i].d; if (con_driver_map[i]) module_put(con_driver_map[i]->owner); __module_get(owner); con_driver_map[i] = csw; if (!vc || !vc->vc_sw) continue; j = i; if (con_is_visible(vc)) { k = i; save_screen(vc); } old_was_color = vc->vc_can_do_color; vc->vc_sw->con_deinit(vc); vc->vc_origin = (unsigned long)vc->vc_screenbuf; visual_init(vc, i, 0); set_origin(vc); update_attr(vc); /* If the console changed between mono <-> color, then * the attributes in the screenbuf will be wrong. The * following resets all attributes to something sane. */ if (old_was_color != vc->vc_can_do_color) clear_buffer_attributes(vc); } pr_info("Console: switching "); if (!deflt) pr_cont("consoles %d-%d ", first + 1, last + 1); if (j >= 0) { struct vc_data *vc = vc_cons[j].d; pr_cont("to %s %s %dx%d\n", vc->vc_can_do_color ? "colour" : "mono", desc, vc->vc_cols, vc->vc_rows); if (k >= 0) { vc = vc_cons[k].d; update_screen(vc); } } else { pr_cont("to %s\n", desc); } retval = 0; err: module_put(owner); return retval; }; #ifdef CONFIG_VT_HW_CONSOLE_BINDING int do_unbind_con_driver(const struct consw *csw, int first, int last, int deflt) { struct module *owner = csw->owner; const struct consw *defcsw = NULL; struct con_driver *con_driver = NULL, *con_back = NULL; int i, retval = -ENODEV; if (!try_module_get(owner)) return -ENODEV; WARN_CONSOLE_UNLOCKED(); /* check if driver is registered and if it is unbindable */ for (i = 0; i < MAX_NR_CON_DRIVER; i++) { con_driver = ®istered_con_driver[i]; if (con_driver->con == csw && con_driver->flag & CON_DRIVER_FLAG_MODULE) { retval = 0; break; } } if (retval) goto err; retval = -ENODEV; /* check if backup driver exists */ for (i = 0; i < MAX_NR_CON_DRIVER; i++) { con_back = ®istered_con_driver[i]; if (con_back->con && con_back->con != csw) { defcsw = con_back->con; retval = 0; break; } } if (retval) goto err; if (!con_is_bound(csw)) goto err; first = max(first, con_driver->first); last = min(last, con_driver->last); for (i = first; i <= last; i++) { if (con_driver_map[i] == csw) { module_put(csw->owner); con_driver_map[i] = NULL; } } if (!con_is_bound(defcsw)) { const struct consw *defconsw = conswitchp; defcsw->con_startup(); con_back->flag |= CON_DRIVER_FLAG_INIT; /* * vgacon may change the default driver to point * to dummycon, we restore it here... */ conswitchp = defconsw; } if (!con_is_bound(csw)) con_driver->flag &= ~CON_DRIVER_FLAG_INIT; /* ignore return value, binding should not fail */ do_bind_con_driver(defcsw, first, last, deflt); err: module_put(owner); return retval; } EXPORT_SYMBOL_GPL(do_unbind_con_driver); static int vt_bind(struct con_driver *con) { const struct consw *defcsw = NULL, *csw = NULL; int i, more = 1, first = -1, last = -1, deflt = 0; if (!con->con || !(con->flag & CON_DRIVER_FLAG_MODULE)) goto err; csw = con->con; for (i = 0; i < MAX_NR_CON_DRIVER; i++) { struct con_driver *con = ®istered_con_driver[i]; if (con->con && !(con->flag & CON_DRIVER_FLAG_MODULE)) { defcsw = con->con; break; } } if (!defcsw) goto err; while (more) { more = 0; for (i = con->first; i <= con->last; i++) { if (con_driver_map[i] == defcsw) { if (first == -1) first = i; last = i; more = 1; } else if (first != -1) break; } if (first == 0 && last == MAX_NR_CONSOLES -1) deflt = 1; if (first != -1) do_bind_con_driver(csw, first, last, deflt); first = -1; last = -1; deflt = 0; } err: return 0; } static int vt_unbind(struct con_driver *con) { const struct consw *csw = NULL; int i, more = 1, first = -1, last = -1, deflt = 0; int ret; if (!con->con || !(con->flag & CON_DRIVER_FLAG_MODULE)) goto err; csw = con->con; while (more) { more = 0; for (i = con->first; i <= con->last; i++) { if (con_driver_map[i] == csw) { if (first == -1) first = i; last = i; more = 1; } else if (first != -1) break; } if (first == 0 && last == MAX_NR_CONSOLES -1) deflt = 1; if (first != -1) { ret = do_unbind_con_driver(csw, first, last, deflt); if (ret != 0) return ret; } first = -1; last = -1; deflt = 0; } err: return 0; } #else static inline int vt_bind(struct con_driver *con) { return 0; } static inline int vt_unbind(struct con_driver *con) { return 0; } #endif /* CONFIG_VT_HW_CONSOLE_BINDING */ static ssize_t store_bind(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { struct con_driver *con = dev_get_drvdata(dev); int bind = simple_strtoul(buf, NULL, 0); console_lock(); if (bind) vt_bind(con); else vt_unbind(con); console_unlock(); return count; } static ssize_t show_bind(struct device *dev, struct device_attribute *attr, char *buf) { struct con_driver *con = dev_get_drvdata(dev); int bind; console_lock(); bind = con_is_bound(con->con); console_unlock(); return sysfs_emit(buf, "%i\n", bind); } static ssize_t show_name(struct device *dev, struct device_attribute *attr, char *buf) { struct con_driver *con = dev_get_drvdata(dev); return sysfs_emit(buf, "%s %s\n", (con->flag & CON_DRIVER_FLAG_MODULE) ? "(M)" : "(S)", con->desc); } static DEVICE_ATTR(bind, S_IRUGO|S_IWUSR, show_bind, store_bind); static DEVICE_ATTR(name, S_IRUGO, show_name, NULL); static struct attribute *con_dev_attrs[] = { &dev_attr_bind.attr, &dev_attr_name.attr, NULL }; ATTRIBUTE_GROUPS(con_dev); static int vtconsole_init_device(struct con_driver *con) { con->flag |= CON_DRIVER_FLAG_ATTR; return 0; } static void vtconsole_deinit_device(struct con_driver *con) { con->flag &= ~CON_DRIVER_FLAG_ATTR; } /** * con_is_bound - checks if driver is bound to the console * @csw: console driver * * RETURNS: zero if unbound, nonzero if bound * * Drivers can call this and if zero, they should release * all resources allocated on con_startup() */ int con_is_bound(const struct consw *csw) { int i, bound = 0; WARN_CONSOLE_UNLOCKED(); for (i = 0; i < MAX_NR_CONSOLES; i++) { if (con_driver_map[i] == csw) { bound = 1; break; } } return bound; } EXPORT_SYMBOL(con_is_bound); /** * con_is_visible - checks whether the current console is visible * @vc: virtual console * * RETURNS: zero if not visible, nonzero if visible */ bool con_is_visible(const struct vc_data *vc) { WARN_CONSOLE_UNLOCKED(); return *vc->vc_display_fg == vc; } EXPORT_SYMBOL(con_is_visible); /** * con_debug_enter - prepare the console for the kernel debugger * @vc: virtual console * * Called when the console is taken over by the kernel debugger, this * function needs to save the current console state, then put the console * into a state suitable for the kernel debugger. * * RETURNS: * Zero on success, nonzero if a failure occurred when trying to prepare * the console for the debugger. */ int con_debug_enter(struct vc_data *vc) { int ret = 0; saved_fg_console = fg_console; saved_last_console = last_console; saved_want_console = want_console; saved_vc_mode = vc->vc_mode; saved_console_blanked = console_blanked; vc->vc_mode = KD_TEXT; console_blanked = 0; if (vc->vc_sw->con_debug_enter) ret = vc->vc_sw->con_debug_enter(vc); #ifdef CONFIG_KGDB_KDB /* Set the initial LINES variable if it is not already set */ if (vc->vc_rows < 999) { int linecount; char lns[4]; const char *setargs[3] = { "set", "LINES", lns, }; if (kdbgetintenv(setargs[0], &linecount)) { snprintf(lns, 4, "%i", vc->vc_rows); kdb_set(2, setargs); } } if (vc->vc_cols < 999) { int colcount; char cols[4]; const char *setargs[3] = { "set", "COLUMNS", cols, }; if (kdbgetintenv(setargs[0], &colcount)) { snprintf(cols, 4, "%i", vc->vc_cols); kdb_set(2, setargs); } } #endif /* CONFIG_KGDB_KDB */ return ret; } EXPORT_SYMBOL_GPL(con_debug_enter); /** * con_debug_leave - restore console state * * Restore the console state to what it was before the kernel debugger * was invoked. * * RETURNS: * Zero on success, nonzero if a failure occurred when trying to restore * the console. */ int con_debug_leave(void) { struct vc_data *vc; int ret = 0; fg_console = saved_fg_console; last_console = saved_last_console; want_console = saved_want_console; console_blanked = saved_console_blanked; vc_cons[fg_console].d->vc_mode = saved_vc_mode; vc = vc_cons[fg_console].d; if (vc->vc_sw->con_debug_leave) ret = vc->vc_sw->con_debug_leave(vc); return ret; } EXPORT_SYMBOL_GPL(con_debug_leave); static int do_register_con_driver(const struct consw *csw, int first, int last) { struct module *owner = csw->owner; struct con_driver *con_driver; const char *desc; int i, retval; WARN_CONSOLE_UNLOCKED(); if (!try_module_get(owner)) return -ENODEV; for (i = 0; i < MAX_NR_CON_DRIVER; i++) { con_driver = ®istered_con_driver[i]; /* already registered */ if (con_driver->con == csw) { retval = -EBUSY; goto err; } } desc = csw->con_startup(); if (!desc) { retval = -ENODEV; goto err; } retval = -EINVAL; for (i = 0; i < MAX_NR_CON_DRIVER; i++) { con_driver = ®istered_con_driver[i]; if (con_driver->con == NULL && !(con_driver->flag & CON_DRIVER_FLAG_ZOMBIE)) { con_driver->con = csw; con_driver->desc = desc; con_driver->node = i; con_driver->flag = CON_DRIVER_FLAG_MODULE | CON_DRIVER_FLAG_INIT; con_driver->first = first; con_driver->last = last; retval = 0; break; } } if (retval) goto err; con_driver->dev = device_create_with_groups(vtconsole_class, NULL, MKDEV(0, con_driver->node), con_driver, con_dev_groups, "vtcon%i", con_driver->node); if (IS_ERR(con_driver->dev)) { pr_warn("Unable to create device for %s; errno = %ld\n", con_driver->desc, PTR_ERR(con_driver->dev)); con_driver->dev = NULL; } else { vtconsole_init_device(con_driver); } err: module_put(owner); return retval; } /** * do_unregister_con_driver - unregister console driver from console layer * @csw: console driver * * DESCRIPTION: All drivers that registers to the console layer must * call this function upon exit, or if the console driver is in a state * where it won't be able to handle console services, such as the * framebuffer console without loaded framebuffer drivers. * * The driver must unbind first prior to unregistration. */ int do_unregister_con_driver(const struct consw *csw) { int i; /* cannot unregister a bound driver */ if (con_is_bound(csw)) return -EBUSY; if (csw == conswitchp) return -EINVAL; for (i = 0; i < MAX_NR_CON_DRIVER; i++) { struct con_driver *con_driver = ®istered_con_driver[i]; if (con_driver->con == csw) { /* * Defer the removal of the sysfs entries since that * will acquire the kernfs s_active lock and we can't * acquire this lock while holding the console lock: * the unbind sysfs entry imposes already the opposite * order. Reset con already here to prevent any later * lookup to succeed and mark this slot as zombie, so * it won't get reused until we complete the removal * in the deferred work. */ con_driver->con = NULL; con_driver->flag = CON_DRIVER_FLAG_ZOMBIE; schedule_work(&con_driver_unregister_work); return 0; } } return -ENODEV; } EXPORT_SYMBOL_GPL(do_unregister_con_driver); static void con_driver_unregister_callback(struct work_struct *ignored) { int i; console_lock(); for (i = 0; i < MAX_NR_CON_DRIVER; i++) { struct con_driver *con_driver = ®istered_con_driver[i]; if (!(con_driver->flag & CON_DRIVER_FLAG_ZOMBIE)) continue; console_unlock(); vtconsole_deinit_device(con_driver); device_destroy(vtconsole_class, MKDEV(0, con_driver->node)); console_lock(); if (WARN_ON_ONCE(con_driver->con)) con_driver->con = NULL; con_driver->desc = NULL; con_driver->dev = NULL; con_driver->node = 0; WARN_ON_ONCE(con_driver->flag != CON_DRIVER_FLAG_ZOMBIE); con_driver->flag = 0; con_driver->first = 0; con_driver->last = 0; } console_unlock(); } /* * If we support more console drivers, this function is used * when a driver wants to take over some existing consoles * and become default driver for newly opened ones. * * do_take_over_console is basically a register followed by bind */ int do_take_over_console(const struct consw *csw, int first, int last, int deflt) { int err; err = do_register_con_driver(csw, first, last); /* * If we get an busy error we still want to bind the console driver * and return success, as we may have unbound the console driver * but not unregistered it. */ if (err == -EBUSY) err = 0; if (!err) do_bind_con_driver(csw, first, last, deflt); return err; } EXPORT_SYMBOL_GPL(do_take_over_console); /* * give_up_console is a wrapper to unregister_con_driver. It will only * work if driver is fully unbound. */ void give_up_console(const struct consw *csw) { console_lock(); do_unregister_con_driver(csw); console_unlock(); } EXPORT_SYMBOL(give_up_console); static int __init vtconsole_class_init(void) { int i; vtconsole_class = class_create("vtconsole"); if (IS_ERR(vtconsole_class)) { pr_warn("Unable to create vt console class; errno = %ld\n", PTR_ERR(vtconsole_class)); vtconsole_class = NULL; } /* Add system drivers to sysfs */ for (i = 0; i < MAX_NR_CON_DRIVER; i++) { struct con_driver *con = ®istered_con_driver[i]; if (con->con && !con->dev) { con->dev = device_create_with_groups(vtconsole_class, NULL, MKDEV(0, con->node), con, con_dev_groups, "vtcon%i", con->node); if (IS_ERR(con->dev)) { pr_warn("Unable to create device for %s; errno = %ld\n", con->desc, PTR_ERR(con->dev)); con->dev = NULL; } else { vtconsole_init_device(con); } } } return 0; } postcore_initcall(vtconsole_class_init); /* * Screen blanking */ static int set_vesa_blanking(char __user *p) { unsigned int mode; if (get_user(mode, p + 1)) return -EFAULT; vesa_blank_mode = (mode < 4) ? mode : 0; return 0; } void do_blank_screen(int entering_gfx) { struct vc_data *vc = vc_cons[fg_console].d; int i; might_sleep(); WARN_CONSOLE_UNLOCKED(); if (console_blanked) { if (blank_state == blank_vesa_wait) { blank_state = blank_off; vc->vc_sw->con_blank(vc, vesa_blank_mode + 1, 0); } return; } /* entering graphics mode? */ if (entering_gfx) { hide_cursor(vc); save_screen(vc); vc->vc_sw->con_blank(vc, -1, 1); console_blanked = fg_console + 1; blank_state = blank_off; set_origin(vc); return; } blank_state = blank_off; /* don't blank graphics */ if (vc->vc_mode != KD_TEXT) { console_blanked = fg_console + 1; return; } hide_cursor(vc); del_timer_sync(&console_timer); blank_timer_expired = 0; save_screen(vc); /* In case we need to reset origin, blanking hook returns 1 */ i = vc->vc_sw->con_blank(vc, vesa_off_interval ? 1 : (vesa_blank_mode + 1), 0); console_blanked = fg_console + 1; if (i) set_origin(vc); if (console_blank_hook && console_blank_hook(1)) return; if (vesa_off_interval && vesa_blank_mode) { blank_state = blank_vesa_wait; mod_timer(&console_timer, jiffies + vesa_off_interval); } vt_event_post(VT_EVENT_BLANK, vc->vc_num, vc->vc_num); } EXPORT_SYMBOL(do_blank_screen); /* * Called by timer as well as from vt_console_driver */ void do_unblank_screen(int leaving_gfx) { struct vc_data *vc; /* This should now always be called from a "sane" (read: can schedule) * context for the sake of the low level drivers, except in the special * case of oops_in_progress */ if (!oops_in_progress) might_sleep(); WARN_CONSOLE_UNLOCKED(); ignore_poke = 0; if (!console_blanked) return; if (!vc_cons_allocated(fg_console)) { /* impossible */ pr_warn("unblank_screen: tty %d not allocated ??\n", fg_console + 1); return; } vc = vc_cons[fg_console].d; if (vc->vc_mode != KD_TEXT) return; /* but leave console_blanked != 0 */ if (blankinterval) { mod_timer(&console_timer, jiffies + (blankinterval * HZ)); blank_state = blank_normal_wait; } console_blanked = 0; if (vc->vc_sw->con_blank(vc, 0, leaving_gfx)) /* Low-level driver cannot restore -> do it ourselves */ update_screen(vc); if (console_blank_hook) console_blank_hook(0); set_palette(vc); set_cursor(vc); vt_event_post(VT_EVENT_UNBLANK, vc->vc_num, vc->vc_num); } EXPORT_SYMBOL(do_unblank_screen); /* * This is called by the outside world to cause a forced unblank, mostly for * oopses. Currently, I just call do_unblank_screen(0), but we could eventually * call it with 1 as an argument and so force a mode restore... that may kill * X or at least garbage the screen but would also make the Oops visible... */ static void unblank_screen(void) { do_unblank_screen(0); } /* * We defer the timer blanking to work queue so it can take the console mutex * (console operations can still happen at irq time, but only from printk which * has the console mutex. Not perfect yet, but better than no locking */ static void blank_screen_t(struct timer_list *unused) { blank_timer_expired = 1; schedule_work(&console_work); } void poke_blanked_console(void) { WARN_CONSOLE_UNLOCKED(); /* Add this so we quickly catch whoever might call us in a non * safe context. Nowadays, unblank_screen() isn't to be called in * atomic contexts and is allowed to schedule (with the special case * of oops_in_progress, but that isn't of any concern for this * function. --BenH. */ might_sleep(); /* This isn't perfectly race free, but a race here would be mostly harmless, * at worst, we'll do a spurious blank and it's unlikely */ del_timer(&console_timer); blank_timer_expired = 0; if (ignore_poke || !vc_cons[fg_console].d || vc_cons[fg_console].d->vc_mode == KD_GRAPHICS) return; if (console_blanked) unblank_screen(); else if (blankinterval) { mod_timer(&console_timer, jiffies + (blankinterval * HZ)); blank_state = blank_normal_wait; } } /* * Palettes */ static void set_palette(struct vc_data *vc) { WARN_CONSOLE_UNLOCKED(); if (vc->vc_mode != KD_GRAPHICS && vc->vc_sw->con_set_palette) vc->vc_sw->con_set_palette(vc, color_table); } /* * Load palette into the DAC registers. arg points to a colour * map, 3 bytes per colour, 16 colours, range from 0 to 255. */ int con_set_cmap(unsigned char __user *arg) { int i, j, k; unsigned char colormap[3*16]; if (copy_from_user(colormap, arg, sizeof(colormap))) return -EFAULT; console_lock(); for (i = k = 0; i < 16; i++) { default_red[i] = colormap[k++]; default_grn[i] = colormap[k++]; default_blu[i] = colormap[k++]; } for (i = 0; i < MAX_NR_CONSOLES; i++) { if (!vc_cons_allocated(i)) continue; for (j = k = 0; j < 16; j++) { vc_cons[i].d->vc_palette[k++] = default_red[j]; vc_cons[i].d->vc_palette[k++] = default_grn[j]; vc_cons[i].d->vc_palette[k++] = default_blu[j]; } set_palette(vc_cons[i].d); } console_unlock(); return 0; } int con_get_cmap(unsigned char __user *arg) { int i, k; unsigned char colormap[3*16]; console_lock(); for (i = k = 0; i < 16; i++) { colormap[k++] = default_red[i]; colormap[k++] = default_grn[i]; colormap[k++] = default_blu[i]; } console_unlock(); if (copy_to_user(arg, colormap, sizeof(colormap))) return -EFAULT; return 0; } void reset_palette(struct vc_data *vc) { int j, k; for (j=k=0; j<16; j++) { vc->vc_palette[k++] = default_red[j]; vc->vc_palette[k++] = default_grn[j]; vc->vc_palette[k++] = default_blu[j]; } set_palette(vc); } /* * Font switching * * Currently we only support fonts up to 128 pixels wide, at a maximum height * of 128 pixels. Userspace fontdata may have to be stored with 32 bytes * (shorts/ints, depending on width) reserved for each character which is * kinda wasty, but this is done in order to maintain compatibility with the * EGA/VGA fonts. It is up to the actual low-level console-driver convert data * into its favorite format (maybe we should add a `fontoffset' field to the * `display' structure so we won't have to convert the fontdata all the time. * /Jes */ #define max_font_width 64 #define max_font_height 128 #define max_font_glyphs 512 #define max_font_size (max_font_glyphs*max_font_width*max_font_height) static int con_font_get(struct vc_data *vc, struct console_font_op *op) { struct console_font font; int rc = -EINVAL; int c; unsigned int vpitch = op->op == KD_FONT_OP_GET_TALL ? op->height : 32; if (vpitch > max_font_height) return -EINVAL; if (op->data) { font.data = kvzalloc(max_font_size, GFP_KERNEL); if (!font.data) return -ENOMEM; } else font.data = NULL; console_lock(); if (vc->vc_mode != KD_TEXT) rc = -EINVAL; else if (vc->vc_sw->con_font_get) rc = vc->vc_sw->con_font_get(vc, &font, vpitch); else rc = -ENOSYS; console_unlock(); if (rc) goto out; c = (font.width+7)/8 * vpitch * font.charcount; if (op->data && font.charcount > op->charcount) rc = -ENOSPC; if (font.width > op->width || font.height > op->height) rc = -ENOSPC; if (rc) goto out; op->height = font.height; op->width = font.width; op->charcount = font.charcount; if (op->data && copy_to_user(op->data, font.data, c)) rc = -EFAULT; out: kvfree(font.data); return rc; } static int con_font_set(struct vc_data *vc, struct console_font_op *op) { struct console_font font; int rc = -EINVAL; int size; unsigned int vpitch = op->op == KD_FONT_OP_SET_TALL ? op->height : 32; if (vc->vc_mode != KD_TEXT) return -EINVAL; if (!op->data) return -EINVAL; if (op->charcount > max_font_glyphs) return -EINVAL; if (op->width <= 0 || op->width > max_font_width || !op->height || op->height > max_font_height) return -EINVAL; if (vpitch < op->height) return -EINVAL; size = (op->width+7)/8 * vpitch * op->charcount; if (size > max_font_size) return -ENOSPC; font.data = memdup_user(op->data, size); if (IS_ERR(font.data)) return PTR_ERR(font.data); font.charcount = op->charcount; font.width = op->width; font.height = op->height; console_lock(); if (vc->vc_mode != KD_TEXT) rc = -EINVAL; else if (vc->vc_sw->con_font_set) { if (vc_is_sel(vc)) clear_selection(); rc = vc->vc_sw->con_font_set(vc, &font, vpitch, op->flags); } else rc = -ENOSYS; console_unlock(); kfree(font.data); return rc; } static int con_font_default(struct vc_data *vc, struct console_font_op *op) { struct console_font font = {.width = op->width, .height = op->height}; char name[MAX_FONT_NAME]; char *s = name; int rc; if (!op->data) s = NULL; else if (strncpy_from_user(name, op->data, MAX_FONT_NAME - 1) < 0) return -EFAULT; else name[MAX_FONT_NAME - 1] = 0; console_lock(); if (vc->vc_mode != KD_TEXT) { console_unlock(); return -EINVAL; } if (vc->vc_sw->con_font_default) { if (vc_is_sel(vc)) clear_selection(); rc = vc->vc_sw->con_font_default(vc, &font, s); } else rc = -ENOSYS; console_unlock(); if (!rc) { op->width = font.width; op->height = font.height; } return rc; } int con_font_op(struct vc_data *vc, struct console_font_op *op) { switch (op->op) { case KD_FONT_OP_SET: case KD_FONT_OP_SET_TALL: return con_font_set(vc, op); case KD_FONT_OP_GET: case KD_FONT_OP_GET_TALL: return con_font_get(vc, op); case KD_FONT_OP_SET_DEFAULT: return con_font_default(vc, op); case KD_FONT_OP_COPY: /* was buggy and never really used */ return -EINVAL; } return -ENOSYS; } /* * Interface exported to selection and vcs. */ /* used by selection */ u16 screen_glyph(const struct vc_data *vc, int offset) { u16 w = scr_readw(screenpos(vc, offset, true)); u16 c = w & 0xff; if (w & vc->vc_hi_font_mask) c |= 0x100; return c; } EXPORT_SYMBOL_GPL(screen_glyph); u32 screen_glyph_unicode(const struct vc_data *vc, int n) { u32 **uni_lines = vc->vc_uni_lines; if (uni_lines) return uni_lines[n / vc->vc_cols][n % vc->vc_cols]; return inverse_translate(vc, screen_glyph(vc, n * 2), true); } EXPORT_SYMBOL_GPL(screen_glyph_unicode); /* used by vcs - note the word offset */ unsigned short *screen_pos(const struct vc_data *vc, int w_offset, bool viewed) { return screenpos(vc, 2 * w_offset, viewed); } EXPORT_SYMBOL_GPL(screen_pos); void getconsxy(const struct vc_data *vc, unsigned char xy[static 2]) { /* clamp values if they don't fit */ xy[0] = min(vc->state.x, 0xFFu); xy[1] = min(vc->state.y, 0xFFu); } void putconsxy(struct vc_data *vc, unsigned char xy[static const 2]) { hide_cursor(vc); gotoxy(vc, xy[0], xy[1]); set_cursor(vc); } u16 vcs_scr_readw(const struct vc_data *vc, const u16 *org) { if ((unsigned long)org == vc->vc_pos && softcursor_original != -1) return softcursor_original; return scr_readw(org); } void vcs_scr_writew(struct vc_data *vc, u16 val, u16 *org) { scr_writew(val, org); if ((unsigned long)org == vc->vc_pos) { softcursor_original = -1; add_softcursor(vc); } } void vcs_scr_updated(struct vc_data *vc) { notify_update(vc); } void vc_scrolldelta_helper(struct vc_data *c, int lines, unsigned int rolled_over, void *base, unsigned int size) { unsigned long ubase = (unsigned long)base; ptrdiff_t scr_end = (void *)c->vc_scr_end - base; ptrdiff_t vorigin = (void *)c->vc_visible_origin - base; ptrdiff_t origin = (void *)c->vc_origin - base; int margin = c->vc_size_row * 4; int from, wrap, from_off, avail; /* Turn scrollback off */ if (!lines) { c->vc_visible_origin = c->vc_origin; return; } /* Do we have already enough to allow jumping from 0 to the end? */ if (rolled_over > scr_end + margin) { from = scr_end; wrap = rolled_over + c->vc_size_row; } else { from = 0; wrap = size; } from_off = (vorigin - from + wrap) % wrap + lines * c->vc_size_row; avail = (origin - from + wrap) % wrap; /* Only a little piece would be left? Show all incl. the piece! */ if (avail < 2 * margin) margin = 0; if (from_off < margin) from_off = 0; if (from_off > avail - margin) from_off = avail; c->vc_visible_origin = ubase + (from + from_off) % wrap; } EXPORT_SYMBOL_GPL(vc_scrolldelta_helper);